Composition comprising a fluorine containing surfactant and perfluoropentane for ultrasound

ABSTRACT

Agents for enhancing the contrast in a diagnostic ultrasound procedure comprise colloidal dispersions of the liquid-in-liquid type, i.e., emulsions or microemulsions, in which the dispersed liquid phase is a high vapor pressure chemical which undergoes a phase change from a dispersed liquid to a highly echogenic dispersed gaseous foam or kugelschaum following administration to an organism. The liquid state of the dispersed phase allows one to manufacture extremely stable, pharmaceutically acceptable emulsions with particle sizes typically below 1000 nm. The gaseous state at body temperature yields highly echogenic microbubbles, typically below 10,000 nm in diameter, which are effective as ultrasound contrast agents. Intravenous, intraarterial, oral, intraperitoneal, and intrauterine dosage forms, methods of administration, and imaging techniques are described.

This application is a continuation of Ser. No. 08/148,284, filed Nov. 8,1993, U.S. Pat. No. 5,595,723 which is a continuation-in-partapplication of Ser. No. 08/008,172, filed Jan. 25, 1993 U.S. Pat. No.5,558,855.

FIELD OF THE INVENTION

The present invention is directed to contrast agents for biomedical usecomprising aqueous colloidal dispersions. More specifically, the presentinvention is directed to liquid in liquid emulsions in which thedispersed liquid undergoes a temperature or pressure activated phaseshift from a dispersed liquid to a dispersed gaseous form which isefficient in reflecting ultrasound energy in a manner which isdiagnostically useful.

BACKGROUND OF THE INVENTION

Various contrast agents for use with diagnostic ultrasound, includingechocardiography, have been described. A review of the subject is foundin Ophir and Parker, Ultrasound in Med. & Biol. (1989), 15:319-333. Theacoustic backscatter arising from these agents, the property typicallyassociated with the contrast effect, can be attributed to uniqueproperties which they possess as solids, liquids or gases. While solidsand liquids reflect sound to a similar degree, gases are known to bemore efficient and are the preferred media for the development ofultrasound contrast agents.

Known liquid agents for ultrasound include emulsions and aqueoussolutions. About these the authors of the above review stated, "the ideaof using liquid emulsions of certain lipids in aqueous vehicles wastested by Fink et al. (1985). Unfortunately, no enhancement ofbackscatter was observable in these experiments."

Known solid agents include collagen microspheres. However, the pooracoustic backscatter of the solid-liquid interface prevents their widespread use.

Known gaseous agents include microbubbles stabilized by the addition ofvarious amphiphilic materials to the aqueous media, by materials thatincrease viscosity, and gaseous precursors, either as solid particles orliposomes. However, the liposomes can only contain water soluble gasesand are thus limited in the stability of the microbubbles they can form,since one of the characteristic physical properties of many of thechemicals which form especially stable microbubbles is immiscibility inwater. The solid particles must be reconstituted immediately before use,requiring extensive preparation, and must be used quickly, since themicrobubbles disappear soon after the particles have completelydissolved. My own prior U.S. patent application Ser. No. 07/761,311 isdirected to methods of determining the relative usefulness of gases asultrasound contrast agents, and identifies particularly useful gases forthat purpose.

One study has been identified which used the injection of a liquid whichboils at a temperature below the boiling point of the organism understudy to enhance the ultrasound Doppler signal (Ziskin MC, BonakdarpourA, Weinstein DP, Lynch PR: Contrast Agents For Diagnostic Ultrasound.Investigative Radiology 7:500-505, 1972). In this study a number ofsolutions or liquids were injected intraarterially into dogs and theDoppler signal detected five cm below the injection site. This studyreported that, "ether, which produced the greatest contrast effect ofany agent that we tried, is a liquid which boils vigorously at bodytemperature and therefore acts as a very active source of bubbles." Thereport further stated that "ether, however, is a toxic substance wheninjected in large amounts. Injections of 20 mL proved fatal in ourexperiments." This paper does not discuss methods of stabilizing anymaterials suitable for later use as ultrasound agents. Non-colloidalether is too toxic for intravenous administration, where the greatestneed for a useful contrast agent exists.

The biocompatability of emulsions which include fluorocarbons is aserious safety concern. For example, Clark et al. (Clark L C, BecattiniF, Kaplan S: Can fluorocarbon emulsions be used as artificial blood?Triangle 11:115-122, 1972) state, in speaking about the choice offluorocarbon, "their vapor pressures range from zero to about 640 torr.Those with vapor pressures over 400 torr, of course, cannot be usedbecause they would boil when infused in the blood stream." Later in thesame article they state, "If a fluorocarbon with a vapor pressure ofover 50 torr is given intravenously, death results in a few hours, andwhen the chest is opened, the lungs do not collapse." The same author,L. C. Clark, reports a similar conclusion exactly twenty years later,"If practical methods cannot be found to prevent or counteract HNCL(hyperinflated non-collapsible lungs), and if HNCL occurs in otherspecies, then only fluorocarbons boiling above 150° C. can be consideredsafe," Clark C L, Hoffmann R E, Davis S L: Response of the rabbit lungas a criterion of safety for fluorocarbon breathing and bloodsubstitutes, Biomat., Art. Cells & Immob. Biotech., 20:1085-1099, 1992.

The stability of liquid-liquid emulsions presents another problem. Abody of knowledge surrounds the stability of emulsions and the abilityto predict stability from solubility; this theory is called the Ostwaldripening theory (Kabalnov A S, Shchukin E D; Ostwald Ripening Theory:Applications To Fluorocarbon Emulsion Stability, Advances in Colloid andInterface Science, 38:69-97, 1992). This paper states, simply, that themore soluble is the dispersed phase liquid of an emulsion in thecontinuous phase, the less stable is the emulsion. These same authorstested the stability of a dodecafluoropentane emulsion at 25° C.(Kabalnov A S, Makarov K N, Shcherbakova O V: Solubility offluorocarbons in water as a key parameter determining fluorocarbonemulsion stability. J Fluorine Chemistry 50:271-284, 1990). Theydetermined that their emulsion had an Ostwald ripening rate of 1.4×10⁻¹⁸cm³ /s. Converting this rate constant into useful terms shows thatKabalnow et al's dodecafluoropentane emulsion, which had an initial sizeof 211 nm, would experience a particle mean diameter growth rate of 11nm/sec or 660 nm/minute. At this rate of particle growth, such anemulsion would have a shelf life of less than a minute, and therefore beunworkable as a commercial product.

Thus, there is a need for an effective ultrasound contrast compositionwith extended shelf life, which is relatively easy to manufacture, whichis biocompatible and convenient to use.

SUMMARY OF THE INVENTION

In order to meet these needs, the present invention is directed tostable colloidal dispersions of the liquid-in-liquid type. The colloidsare ideally composed of a liquid dispersed phase which has a boilingpoint below the body temperature of the organism on which an ultrasoundcontrast study is desired, typically about 37°-40° C. These emulsionsare preferably composed of a dispersed phase liquid which has a boilingpoint between -20° and 37° C.

Preferably the liquid dispersed phase is selected from the group ofchemicals consisting of aliphatic hydrocarbons, organic halides orethers, or combinations thereof, which have six or fewer carbon atomsand an upper limit of molecular weight of about 300. Among organichalides, the fluorine-containing chemicals are preferred, since theyform stable emulsions and are relatively non-toxic. Especially preferredare n-pentane, isopentane, neopentane, cyclopentane, butane,cyclobutane, decafluorobutane, dodecafluoropentane,dodecafluoroneopentane, perfluorocyclopentane and mixtures thereof.Preferably, the colloidal dispersion contains the dispersed phase at aconcentration of 0.05 to 5.0% w/v. Optimally, the concentration range is0.5 to 3.5% w/v.

The colloidal dispersion can be stabilized by the addition of variousamphiphilic materials, including anionic, nonionic, cationic, andzwitterionic surfactants, which typically lower the interfacial tensionbetween the dispersed liquid and water to below 26 dynes/cm. Optimally,these materials are nonionic, synthetic surfactant mixtures, containinga fluorine-containing surfactant, such as the Zonyl brand series and apolyoxypropylene-polyoxyethylene glycol nonionic block copolymer.

The liquid continuous phase of the colloidal dispersion comprises anaqueous medium. This medium can contain various additives to assist instabilizing the dispersed phase or in rendering the formulationbiocompatible. Acceptable additives include acidifying agents,alkalizing agents, antimicrobial preservatives, antioxidants, bufferingagents, chelating agents, suspending and/or viscosity-increasing agents,including triodobenzene derivatives, such as iohexol or iopamidol, andtonicity agents. Preferably, agents to control the pH, tonicity, andincrease viscosity are included. Optimally, a tonicity of at least 250mOsm is achieved with an agent which also increases viscosity, such assorbitol or sucrose.

The colloidal dispersions are typically formed by comminuting asuspension of the dispersed phase in the continuous phase by theapplication of mechanical, manual, or acoustic energy. Condensation ofthe dispersed phase into the continuous phase is also acceptable. Thepreferred mode is to use high pressure comminution.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to agents that enhance the contrast in anultrasound image generated for use in medical and veterinary diagnosis.These agents are comprised of biocompatible colloidal dispersions inwhich the dispersed phase is a liquid under the conditions of themanufacturing process and which undergoes a phase shift to become adispersed gas or kugelschaum at or about the time of administration tothe organism under study.

In order to provide a clear and consistent understanding of the presentinvention and claims, including the scope given to such terms, thefollowing definitions relating to the invention are provided:

Colloidal Dispersion: A system having at least one substance as a liquidor gas (the dispersed phase) which is immiscible and finely divided anddistributed evenly throughout at least one second substance which formsthe dispersion medium or continuous liquid phase.

Biocompatible: Capable of performing functions within or upon a livingorganism in an acceptable manner, without undue toxicity orphysiological or pharmacological effects.

Liquid: The state of matter in which a substance or substancesexhibit(s) a characteristic readiness to flow, little or no tendency todisperse, and relatively high incompressibility.

Gas: The state of matter of a substance or substances which isdistinguished from the solid or liquid states by very low density andviscosity, relatively great expansion and contraction with changes intemperature and pressure, and the spontaneous tendency to becomedistributed uniformly throughout any container.

Phase Shift: A change of state between liquid and gas due to changes intemperature and/or pressure.

Kuqelschaum: One of the two forms of foams in the classification ofManegold (Manegold, E. "Schaum, Strassenbau, Chemie und technik."Heidelberg, 1953, which is incorporated herein by reference).Specifically, the kugelschaum or spherical foam, consists of widelyseparated spherical bubbles and is distinct from the polyederschaum orpolyhedral foams, which consist of bubbles that are nearly polyhedral inshape, having narrow lamellar films of very low curvature separating thedispersed phase.

Low Boiling Liquid: A liquid with a boiling point, under standardpressure conditions, below 37° C. Low boiling liquids useful in theinvention include, but are not limited to, those selected from thechemical group: Isobutane; Ethane, 1-chloro-1,1,2,2-tetrafluoro;Isobutylene; Dimethyl amine, hexafluoro; 1-Butene; 1,3-Butadiene;Cyclobutane, octafluoro; Propylene, 3-fluoro; Dimethyloxonium chloride;Methanesulfenylchloride, trifluoro; n-Butane; Propane, 2,2-difluoro;Ethane, nitro-pentafluoro; 2-Butene {trans}; 1,2-Benzanthracene,4-methyl; Propane, 1,1,1,2,2,3-hexafluoro; Azomethane; Phthalic acid,tetrachloro; Trimethyl amine; Cyclobutene, perfluoro; Ethane,1,1-dichloro-1,2,2,2-tetrafluoro; 2-Butene {cis}; Butane, decafluoro;Acetylene-bromo; 1-Butene, perfluoro; Benzoyl chloride, pentachloro;Vinyl acetylene; 1,3-Butadiene, hexafluoro; Methanethiol; Carbonsuboxide; Ethane, 2-chloro-1,1,1-trifluoro; Dimethyl amine; 1-Butyne;Methane, dichloro-fluoro; Neopentane; Neopentane, perfluoro; Butadiyne;1,2-Butadiene; Ethyl methyl ether; 1,3-Butadiene, 2-fluoro;Crotononitrile; Cyclobutane; Isobutane, 1,2-epoxy-3-chloro; Methyl vinylether; Ethane, Chloro; Diazoethane, 1,1,1-trifluoro; Methane, disilano;Ethyl amine; 2,3-Dimethyl-2-norbornano; Borine, trimethyl; 1-Butene,3-methyl; Cyclopropane, 1,1-dimethyl; Acetaldehyde; Acetyl flouride;Borine, dimethyl, methoxy; Ethylene, 1,2-dichloro-1,2-difluoro; Methane,difluoro-iodo; Propylene, 2-chloro; Carvone- {d}; Methane,trichlorofluoro; 1,3-Dioxolane-2-one, 4-methyl; Methane, dibromodifluoro; Methane, chloro difluoro nitro; 2-Pentanone, 4-amino-4-methyl;Propane, heptafluoro-1-nitro; Hydrocyanic acid; 3-Butene-2-one, 4-phenyl{trans}; 1,5-Heptadiyne; 1,4-Pentadiene; 2-Butyne; Butane, 2-methyl;2-Methyl butane; Cyclopropane, 1,2-dimethyl {trans, dl}; Toluene,2,4-diamino; 1-Butyne, 3-methyl; 1-Pentene; Pentane, perfluoro;1-Pentene, 3-bromo; Ethane, 1,2-difluoro; 1-Butene, 2-methyl; Formicacid, methyl ester; Methane sulfonyl chloride, trifluoro; Diaziridine,3-ethyl-3-methyl; Ethane, 1,1-dichloro-1-fluoro; Propane, 2-amino;Butane, 1-fluoro; Methyl isopropyl ether; Propylene, 1-chloro;Butyraldehyde, 2-bromo; bis-(imethyl phosphino) amine; 1,3-Butadiene,2-methyl; 1-Butene-3-yne, 2-methyl; Isoprene; Propane, 1,2-epoxy;Cyclopropane, ethyl; Ethyl ether; Dimethyl disulfide, hexafluoro;Propane, 2-chloro; Ethyl hypochlorite; Methane, bromo-chloro-fluoro;Piperidine, 2,3,6-trimethyl; n-Pentane; Cyclobutane, methyl; 2-Pentene{trans}; Ethyl methyl amine; 2-Pentene {cis}; Cyclopropane, 1,2-dimethyl{cis}; Ethylene, 1,1-dichloro; Hydrazoic acid; Methyl sulfide;Propylene, 1-chloro-{trans}; Ethylene, 1,1-dichloro-2-fluoro; 2-Butene,perfluoro; Ethyl nitrite; Methane, bromo fluoro; Cyclopentene, 3-chloro;1-Nonene-3-yne; Cyclopropane, 1,2-dimethyl {trans, l}; 1-Pentene,perfluoro; Styrene, 3-fluoro; Acetylene-diido; 1,3-Butadiene,1,2,3-trichloro; Methane, chloro dinitro; Ethyl vinyl ether; Dimethylethyl amine; and 1,2,3-Nonadecane tricarboxylic acid.

High Vapor Pressure Chemical: A chemical with a sufficiently high vaporpressure that colloidal dispersions of the chemical as a liquid contain,at the body temperature of an organism undergoing an ultrasoundexamination, a sufficient quantity of the chemical as a gaseousdispersion to provide a diagnostically useful alteration in theultrasound data obtained during an examination. High vapor pressurechemicals include low boiling liquids, a preferred embodiment of thepresent invention. Chemicals with vapor pressures at ambient temperatureof above 20 Torr (typically having boiling points below 135° C.) areanother preferred embodiment. The latter class of chemicals which areuseful in this invention include, but are not limited to: perfluorinatedn-alkanes, cycloalkanes, and branched alkyl compounds containing up tonine carbons (nonane; B.P. 125° C.); alkyl hydrocarbons containing up toten carbons, such as n-decane; ethers, other organic halides, andalcohols.

Aliphatic Hydrocarbons: The group of alkane, alkene, alkyne,cycloalkane, and cycloalkene organic compounds. Only the members of thegroup with six or fewer carbon atoms have boiling points below 37° C.and are thus capable of undergoing a liquid to gas phase transitionafter administration to a subject. Aliphatic hydrocarbons useful in theinvention include, but are not limited to, those selected from thechemical group: Isobutane; Isobutylene; 1-Butene; 1,3-Butadiene;n-Butane; 2-Butene {trans}; 2-Butene {cis}; Vinyl acetylene; 1-Butyne;Neopentane; Butadiyne; 1,2-Butadiene; Cyclobutane; 1-Butene, 3-methyl;Cyclopropane, 1,1-dimethyl; 1,3-Dioxolane-2-one, 4-methyl;3-Butene-2-one, 4-phenyl {trans}; 1,5-Heptadiyne; 1,4-Pentadiene;2-Butyne; Butane, 2-methyl; Cyclopropane, 1,2-dimethyl {trans, dl};1-Butyne, 3-methyl; 1-Pentene; 1-Butene, 2-methyl; 1,3-Butadiene,2-methyl; 1-Butene-3-yne, 2-methyl; Isoprene; Cyclopropane, ethyl;n-Pentane; Cyclobutane, methyl; 2-Pentene {trans}; 2-Pentene {cis};Cyclopropane, 1,2-dimethyl {cis}; and 1-Nonene-3-yne.

Organic Halides: The group of compounds containing at least one carbonor sulfur atom and at least one halogen atom, i.e., chlorine, bromine,fluorine, or iodine. Only the members of the group with six or fewercarbon atoms are capable of undergoing a phase transition uponadministration to an organism with a body temperature of 37° C. Organichalides useful in the invention include, but are not limited to:Methane, tetrafluoro; Methane, nitrosotrifluoro; Methane, trifluoro;Methane, chlorotrifluoro; Ethane, hexafluoro; Ethane, perfluoro;Methane, fluoro; Ethylene, tetrafluoro; Sulfur hexafluoride;Trifluoroacetonitrile; Methane, bromotrifluoro; Methane, difluoro;Propyne, 3,3,3-trifluoro; Ethane, 1,1,1-trifluoro; Ethane,nitrosopentafluoro; Methane, chloro-difluoro; Allene, tetrafluoro;Ethane, 1-chloro-1,1,2,2,2-pentafluoro; Ethane, chloropentafluoro;Ethane, fluoro; Dimethylamine, perfluoro; Propane, perfluoro; Ethylamine, perfluoro; Trifluoromethyl peroxide; Azomethane, hexafluoro;Methane, nitrotrifluoro; Methane, dichlorodifluoro; Propylene,perfluoro; Acetone, hexafluoro; Ethane, 1,1,1,2-tetrafluoro; Ethylene,1-chloro-1,2,2-trifluoro; Ethylene, chlorotrifluoro; Ethane,1,1-difluoro; 2-Butyne, perfluoro; Methane, iodotrifluoro;Trifluoromethyl sulfide; Methane sulfonyl fluoride, trifluoro; Methane,(pentafluorothio)trifluoro; Methane, bromodifluoronitroso; Propane,heptafluoro-1-nitroso; Ethane, 1-chloro-1,1,2,2-tetrafluoro;Cyclobutane, octafluoro; Propylene, 3-fluoro; Methanesulfenylchloride,trifluoro; Propane, 2,2-difluoro; Ethane, nitropentafluoro; Propane,1,1,1,2,2,3-hexafluoro; Cyclobutene, perfluoro; Ethane,1,1-dichloro-1,2,2,2-tetrafluoro; Butane, decafluoro; 1-Butene,perfluoro; 1,3-Butadiene, hexafluoro; Ethane, 2-chloro-1,1,1-trifluoro;Methane, dichloro-fluoro; 1,3-Butadiene, 2-fluoro; Diazoethane,1,1,1-trifluoro; Acetyl flouride; Ethylene, 1,2-dichloro-1,2-difluoro;Methane, difluoroiodo; Methane, trichlorofluoro; Methane,dibromodifluoro; Methane, chlorodifluoro nitro; Propane,heptafluoro-1-nitro; Pentane, perfluoro; Neopentane, perfluoro; Ethane,1,2-difluoro; Methane sulfonylchloride, trifluoro; Ethane,1,1-dichloro-1-fluoro; Butane, 1-fluoro; Dimethyl disulfide, hexafluoro;Methane, bromochlorofluoro; Ethylene, 1,1-dichloro-2-fluoro; 2-Butene,perfluoro; Methane, bromofluoro; 1-Pentene, perfluoro; Styrene,3-fluoro; Boron fluoride dihydrate; Butyne,2-chloro-1,1,1,4,4,4-hexafluoro; Ethane, 1,1,2,2-tetrafluoro; Ethane,1,1,2-trichloro-1,2,2-trifluoro; Ethane,1,2-dichloro-1,1,2,2-tetrafluoro; Ethane, 2-chloro, 1,1-difluoro;Ethane, dichlorotrifluoro; Ethylene, 1,2-difluoro; Ethylene,dichlorodifluoro; Methane, chlorofluoro; and Propyl,1,1,1,2,3,3-hexafluoro-2,3-difluoro.

Ethers: The class of organic compounds in which two hydrocarbon groupsor derivatives thereof are linked by an oxygen atom. For the purposes ofthe present invention the following are examples of some, but notnecessarily all, ethers which can be used: methyl ether, ethyl methylether, methyl vinyl ether, methyl isopropyl ether, 1,2-epoxypropylether, diethyl ether, ethyl vinyl ether, and vinyl ether.

Fluorine-Containing Compounds: A compound containing at least onefluorine atom. Useful fluorine-containing compounds are listed as abovelisted organic halides.

The colloidal dispersions of the invention can be emulsions ormicroemulsions.

Emulsion: A colloidal dispersion of one immiscible liquid dispersed inanother liquid in the form of droplets, whose diameter, in general, arebetween 100 and 3000 nm and which is typically optically opaque, unlessthe dispersed and continuous phases are refractive index matched. Suchsystems possess a limited stability, generally defined by theapplication or relevant reference system, which may be enhanced by theaddition of amphiphilic materials or viscosity enhancers.

Microemulsion: A stable liquid monophasic and optically isotropiccolloidal dispersion of water and water-immiscible liquids stabilized byamphiphilic materials in which the dispersions have appreciable lightscattering properties (meaning they can appear optically clear or milkybut are reddish or yellowish if observed by transmitted light) and thediameters of the particles are, in general, between 5 and approximately140 nm.

In a preferred embodiment of the present invention, the colloidaldispersion contains one or more amphiphilic materials to improve thestability of the formulation.

Amphiphilic Material: A substance which is strongly adsorbed at aninterface and which normally produces a dramatic reduction in theinterfacial tension with small changes in the bulk phase concentration.Examples include synthetic surfactants, naturally occurring materialssuch as biocompatible proteins, lipids, sterols, alginates, cellulosederivatives, and finely divided organic or inorganic particulate solids.

Organic Particulate Solids: include sugars, proteins, amino acids,lipids, nucleic acids, and others.

Inorganic Particulate Solids: include aluminas, carbonates,bicarbonates, silicates, aluminasilicates, phosphates, and others.

Interface: The region or boundary of the physical world that liesbetween two distinct and identifiable phases of matter, herein limitedto liquid-liquid, liquid-solid, solid-gas, and liquid-gas.

Interfacial Tension: The force per length which exists at the interfacebetween two distinct and identifiable phases of matter.

Stability: The time lapse from initial preparation and packaging duringwhich a colloidal dispersion continues to fulfill all chemical andphysical specifications with respect to identity, strength, quality, andpurity which have been established according to the principles of GoodManufacturing Practice, as set forth by appropriate governmentalregulatory bodies.

Surfactants: The group of amphiphilic materials which are manufacturedby chemical processes or purified from natural sources or processes.These can be anionic, cationic, nonionic, and zwitterionic, and includethe following distinct chemical groups:

Group 1: Acetamide Monoethanolamine (Mea), Acetylenic Diol, AcetylenicDiol Blend, Proprietary, Alcohol Alkoxylates, Alcohol And Alcohol EtherSulfates, Alcohol-Ethoxylated-Propoxylated Surfactant Defoamer, AlcoholEthoxysulfates, Alcohol, Oxyalkylated, Alcohol, PolyoxyethaylatedSynthetic, Alcohols, Alkoxylated Linear, Alcohols, Detergent, Alcohols,Ethoxylated, Alcohols, Low-Foam Alkoxylated, Alcohol Sulfates, AliphaticAlcohols, Ethoxylated Branched, Aliphatic Diamines, AliphaticEthoxylate, Linear, Aliphatic Nonionics, Alkanolamides, AlkoxylatedLinear Alcohol Carboxylic, Acid Sodium Salts, Alkoxypolyalkoxyethanol,Alkyl Acid Phosphates, Alkyl Alkoxylate, Fluorinated, Alkylamine,Polyoxyethylated, Alkyl Amphoteric, Fluorinated, Alkylaryl Polyether,Alkylaryl Polyethoxylate-Sodium Salt Of Alkylsulfonatedalkylate Blend,Alkylaryl Polyoxyethylene Ether, Alkylaryl-Polyoxyethylene-Glycol,Phosphate Ester Surfactants, Solubilizers, Alkylaryl PolyoxyethyleneGlycols, Alkylaryl Sulfonate;

Group 2: Alkylate Sulfonate, Linear, Alkylbenzenes, Alkyl Betaine, AlkylEsters, Fluorinated, Alkyl Ether Sulfates, Alkyl Ethoxylate, AlkylImidazolines, Alkylolamides, Fatty Acid, Alkylolamides, Methyl Cocoate,Alkylphenol Alkoxylates, Alkylphenol Condensate, Ethoxylated,Alkylphenols, Ethoxylated, Alkylphenols, Polyoxyethylated, AlkylPolyglycosides, Alkyl Quaternary, Fluorinated, Alkyl Sulfate, AlkylSulfate, Lauryl Alcohol, Amidoamine Methosulfate, AmidopropylamineOxide, Amine Condensate, Amine Oxides, Amines, Primary, Ethoxylated,Amines, Tertiary, Ammonium Cumene Sulfonate, Ammonium Ether Sulfate,Ammonium Laureth Sulfate, Ammonium Lauryl Sulfate, Ammonium LaurylSulfosuccinate, Ammonium Xylene Sulfonate, Amphoterics;

Group 3: Amphoteric Salts, Anionic And Nonionic Surfactants,Anionic-Nonionic Blend Emulsifiers, Anionic-Nonionic Blends, AromaticAnd Aliphatic Phosphate Esters, Avocadamine Dea And Avocado Oil,Betaines, Betaines, Amphoteric, Calcium Stearoyl 2-Lactylate, CapricDiethanolamide, Carboxylated Alkyl, Aryl-Alkyl Polyethoxylates, CastorGlycerides, Polyoxyethylated, Hydrogenated, Castor Oil, Ethoxylated,Castor Oil, Ethoxylated, Hydrogenated, Castor Oil, Refined Castor Oil,Sulfonated, Cationic Surfactant, Cetyl Acetate And Acetylated LanolinAlcohol, Cocamide, Diethanolamine (Dea), Cocamide Monoethanolamine(Mea), Cocamidopropyl Amine Oxide, Cocamidopropyl Betaine,Cocamidopropyl Dimethylamine, Cocamphocarboxyglycinate, Cocoamine,Ethoxylated, Cocoamine Oxide, Cocoamine, Polyoxyethylated;

Group 4: Cocodiethanolamide, Coconut Acid Ester Of Sodium Isethionate,Coconut Amide Nonionics, Coconut Diethanolamide (68603-42-9), CoconutMonoethanolamide, Coconut Oil Diethanolamine Condensate, CocoylImidazoline, Cocoyl Sarcosine, Cyclodextrins, Alpha, Beta, Gamma,Deceth-4 Phosphate, Decyl Alcohol, Ethoxylated, Decyl-Diphenyl OxideDisulfonic Acid, Defoamer Blend, Demulsifiers (Emulsion Breakers),Diacetyltartaric Acid Esters Of Monoglycerides, Dialkyl(C12 C18)Dimethylammonium Chloride, Dicarboxylcocoimidazoline Compound,Diethanolamines, 2:1, Diethanolamine Lauryl Sulfate, Diethylene GlycolMonosterate, 3,5-Dimethyl-1-Hexyn-3-Ol, 3,6-Dimethyl-4-Octyne-3,6-Diol,Dimethyl Tertiary Amines, Dinonylphenols;

Group 5: Polyoxyethylated, Disodium Cocamido-Ethanolamine Sulfosuccinate(Mea), Disodium Cocamido Iso-Propanolamine Sulfosuccinate (Mipa),Disodium Ethoxylated Alcohol Half Ester Of Sulfosuccinic Acid, DisodiumEthoxylated Nonylphenol Half Ester Of Sulfosuccinic Acid, DisodiumLauramido-Ethanolamine Sulfosuccinate (Mea), Disodium LaurethSulfosuccinate, Disodium Oleamido-Ethanolamine Sulfosuccinate(Mea),Disodium Oleamido-Polyethyleneglycol-2-Sulfosuccinate, DisodiumOleamido-Iso-Propanolamine Sulfosuccinate (Mipa), DisodiumRicinoleamidoethanolamine Sulfosuccinate (Mea), DisodiumUndecylenamido-ethanolamine Sulfosccinate (Mea), Dispersing Agents,Distearyldimethylammonium Chloride, Ditallowdimethylammonium Chloride,Dodecylbenzenesulfonic Acid;

Group 6: Dodecyldiphenylether Disulfonic Acid, Dodecyldiphenyl OxideDisulfonic Acid, Dodecyl Diphenyl Oxide Sulfonate, Dodecylphenols,Emulsified Surfactant Defoamer, Emulsifiers, Emulsion Stabilizers,Esters, Ethanol-2-Phenolxy, Ether Sulfate, Ethoxylate, Complex,Ethoxylated Acetylenic Diol, Ethoxylated Alcohol Blends, EthoxylatedAlcohol Defoamer, Ethoxylated Derivatised Phenols,Ethoxylated-Emulsified Surfactant Defoamer, Ethoxylated Esters,Ethoxylated Fatty Acid Esters, Ethoxylated Fatty Alcohol EthoxylatedLanolin Alcohols, Ethoxylated Polyoxypropylene Glycols,Ethoxylated-Propoxylated Block Copolymers Ethoxylated-Propoxylated BlockPolymers, Ethoxylated-Propoxylated Sufactant Defoamer, EthoxylatedSulfonate, Ethoxylated Surfactant Antifoam, Ethoxylated Surfactant BlendDefoamer, Ethoxylated Surfactant Defoamer;

Group 7: Ethoxylates, Nonionic, Ethoxylate Sulfate, Ammonium Salt,Ethoxylate Sulfate, Lauryl Alcohol, Ethylene Glycol Distearate, EthyleneGlycol Monostearate, Ethylene Oxide Adduct, Ethylene Oxide Condensate,Ethylene Oxide-Nonylphenol Adduct, Fatty Acid Alkoxylates, Fatty Acids,Polyoxyethylated, Fatty Alcohol-Ethylene Oxide Condensates, FattyAlcohol Nonionic, Fatty Alcohol, Polyoxyethylated, Fatty Amides AndBisamides, Fatty Amine Alkoxylates, Fatty Diethanolamides, FluorinatedSurfactants, Fluoroalkyl Carboxylates, Fluorocarbons, Fluorosurfactants,Foamers, Glycerol Monooleate, Glycerol Monostearate, HexadecylDiphenylether Disulfonic Acid, Hydrotropes, Xylene, Imidazolines,Isoalcohol, Alkoxylated, Isopropylamine;

Group 8: Dodecyclbenzene Sulfonate, Isostearyl Alcohol, Alkoxylated,Isostearyl Lactate, Jojoba Oil Derivatives, Kerosene (Deodorized)Organic Defoamer, Lactamide Ethanolamine (Mea), Lanolin, Ethoxylated,Lauramide Diethanolamine (Dea), Lauramide Ethanolamine (Mea), LauramideNonionics, Lauramidopropyl Amine Oxide, Lauramidopropyl Betaine,Lauramidopropyl Dimethylamine, Lauramine Oxide, Lauric Acid,Ethoxylated, Lauric Acid Monoisopropanolamide, Lauric Diethanolamide,Lauric-Myristic Diethanolamide, Lauroyl Sarcosine, Lauryl Alcohol,Ethoxylated, Lauryl Monoethanolamide, Lauryl Polyglucose, Ligninamine,Lignin (Sulfonated), Sodium Salts;

Group 9: Linear Alcohols, Ethoxylated, Linoleic Diethanolamide,Methylbis- (Hydr.Tallowamidoethyl)-2-Hydroxyethylammonium MethylSulfate, Methylbis (Tallowamidoethyl)-2-Hydroxypropyl Ammonium MethylSulfate, Methyl-1-Oleylanidoethyl-2-Olelimidazolinium Methyl Sulfate,Methyl-1-Tallowamidoethyl-2-Tallowimidazolinium Methyl Sulfate, MineralSeal Oil-Based Defoamer, Monocarboxylcocoimidazoline Compound,Monodiglycerides, Monoglyceride Citrate, Monoglycerides, Ethoxylated,Naphthalene-Formaldehyde Condensate (Sulfonated), Sodium Salt, NonionicSurfactant Nonyldiphenyl Ether Disulfonic Acid, Nonylphenol Ethoxylate,Nonylphenol Nonionics, Nonylphenols, Polyoxyethylated;

Group 10: Nonylphenoxypoly(Ethyleneoxy) Ethanol (Sulfated), AmmoniumSalt, Octylphenol Ethoxylate, Octylphenols, Polyoxyethylated, OctylSalicylate, Oleamide Diethanolamini (Dea), Oleamidopropyl Dimethylamine,Oleic Acid,Ethoxylated Oleic Diethanolamide, N-Oleoylsarcosine, OleylAlcohol Phosphate Ester, Oleyl Alcohol, Polyoxyethylated,Oleylamine,Ethoxylated, Organic Phosphate Esters, Free Acids Of, OrganicSalt, Organic-Silicone Blend, Antifoam, Organic-Silicone Defoamer,Oxazolines, Paper Additives, Peg-15 Cocamine Phosphate Oleate,Perfluoroalkyl Sulfonates, Phosphate Acid Esters, Aliphatic Base,Phosphate Acid Ester, Aromatic Base, Phosphate Acid Esters, AromaticHydrophobic Base, Phosphate Acid Esters, Fatty Alcohol, Phosphate AcidEsters, Linear Alcohol, Phosphated Alcohol Ethoxylate, Phosphate Ester,Aliphatic Hydrophobic Base;

Group 11: Phosphate Ester-Free Acids, Phosphate Ester, Partial SodiumSalt, Phosphate Esters, Phthalic Glycerol Alkyd Resin, Modified,Polyacrylic Acid, Polyalkylene Oxide, Polyether, Alkoxylated, Polyether,Block Polymer, Polyethers, Polyethoxylated Amines, Polyethoxylated FattyAcids, Polyethylene Emulsions, Polyethylene Glycol Dioleates,Polyethylene Glycol Ditallate, Polyethylene Glycol Esters, PolyethyleneGlycol Monolaurate, Polyethylene Glycol Monooleate, Polyglycerol Esters,Polyoxyethylene Caster Oil, Polyoxyethylene Cocoamine, PolyoxyethyleneOleic Acid, Polyoxyethylene Stearic Acid, Polyoxyethylene Tallowamine,Polypropylene Glycol Distallate;

Group 12: Polypropylene Glycol Ester, Polysodium Vinylsulfonate,Potassium And Sodium Soaps, Potassium Cocoates, PotassiumToluenesulfonate, Propoxylated Alcohol, Propoxylated PolyoxyethyleneGlycols, Pyridine-3-Sulfonic Acid, Quaterinaries, QuaternaryAlkylamines, Quaternary Ammonoim Compounds, Quaternary Ammonium Salts,Quaternary Biocides, Ricinoleamide Diethanolamine (Dea), RicinoleicDiethanolamide, Silicone Antifoams, Silicone Coatings, SiliconeDefoamers, Silicone Emulsions, Silicone Fluids, Silicone-GlycolCopolymers, Sodium Alkylarylsulfonate Sodium Alkylnaphthalenesulfonate,Sodium Bistridecyl Sulfosuccinate, Sodium Butoxyethoxy Acetate, SodiumCapryl Lactylate, Sodium N-Cocoyl-N-Methyltaurate;

Group 13: Sodium Cocoylsarcosinate, Sodium Cumenesulfonate, SodiumDecyldiphenyl Ether Sulfonate, Sodium Diamyl Sulfosuccinate, SodiumDibutyl Sulfosuccinate, Sodium Dicarboxyethylcoco PhosphoethylImidazoline, Sodium Dicyclohexyl Sulfosuccinate, Sodium DihexylSulfosuccinate, Sodium Diisobutyl Sulfosuccinate, SodiumDioctylsulfosuccinate, Sodium Dioctylsulfosuccinate And Mineral Spirits,Sodium Dioctylsulfosuccinate And Propylene Glycol, SodiumDodecylbenzenesulfonates, Sodium Dodecyldiphenyl Ether Sulfonate, Sodium2-Ethylhexyl Sulfate, Sodium Isodecyl Sulfosuccinate, Sodium IsostearoylLactylate, Sodium Laureth Sulfate, Sodium Lauroyl Lactylate, SodiumLauroylsarcosinate, Sodium Lauryl Sulfate, Sodium Lauryl Sulfoacetate,Sodium N-Methyl-N-Oleoyltaurate, Sodium Naphthalene Sulfonate, Sodium1-Octane Sulfonate, Sodium C14-16 Olefin Sulfonates, SodiumPolyacrylate, Sodium Stearoyl Lactylate, Sodium Tetradecyl Sulfate,Sodium Toluenesulfonate, Sodium Toluene-Xylenesulfonate, SodiumVinylsulfonate, Sodium Xylene Sulfonate, Sorbitan And EthoxylatedSorbitan Esters, Sorbitan Oleate, Sorbitan Stearate, Soya Amine;

Group 14: Polyoxyethylated, Soyamide Diethanolamine (Dea), StearalkoniumChloride, Iso-Stearamidopropyl Bentaine, Stearamidopropyl Dimethylamine,Stearamidopropyl Pg-Dimonium Chloride Phosphate, Stearic AcidDiethanolamide, Stearic Acid, Ethoxylated; and

Group 15: Stearic Acid Monoethanolamide, Stearic Imidazoline,Stearylamine,Ethoxylated, Succinimides,Basic, Sucrose Esters, SulfateEster, Sulfates And Ether Sulfates, Sulfobetaines, Sulfonates,Sulfonates,Dodecylbenzene, Sulfonic Acid, Linear Alkyl(C-12) Benzene,Sulfosuccinamates, Sulfosuccinate Esters, Sulfosuccinates, Surfactant,Oil Defoamer, Surfactant Solution Defoamer, Surfactants, Low-Foaming,Surfactants, Soluble-Oil-Base, Polyoxyethylated Tall Oil Fatty Acid,Ethoxylated Tall Oil Fatty Acids, Tall Oil Imidazoline, EthoxylatedTallowamine, Polyoxyethylated Tallowamine, DihydrogenatedTallowdimethylammonium Chloride, Dihydrogenated TallowdimethylammoniumMethyl Sulfate, Tetrahydroxy-propylethylenediamene, Tert-Thioethoxylate,Toluenesulfonic Acid, Ethoxylated Tridecyl Alcohol,Tridecyloxypoly-(Ethyleneoxy)-Ethanol, TriethanolamineLauroylsarcosinate, Triethanolamine Lauryl Sulfate, TriethanolaminePhosphate Ester, Trimethylnonyl Ether of Polyethylene Glycol, WettingAgents, Yucca Extract.

The continuous phase of the colloidal dispersion of the presentinvention is an aqueous medium.

Aqueous Medium: A water-containing liquid which can containpharmaceutically acceptable additives such as acidifying agents,alkalizing agents, antimicrobial preservatives, antioxidants, bufferingagents, chelating agents, complexing agents, solubilizing agents,humectants, solvents, suspending and/or viscosity-increasing agents,tonicity agents, wetting agents or other biocompatible materials. Atabulation of ingredients listed by the above categories, can be foundin the U.S. Pharmacopeia National Formulary, 1990, pp. 1857-1859, whichis incorporated herein by reference.

A preferred embodiment of the present invention includes the use of atleast one amphiphilic material from the groups consisting ofbiocompatible proteins, fluorine-containing surfactants,polyoxypropylene-polyoxyethylene glycol nonionic block copolymers, andsurfactants.

Polyoxvypropylene-Polyoxvethylene Glycol Nonionic Block Copolymers: Thesurfactants which are available from BASF Performance Chemicals,Parsippany, N.J. under the trade name Pluronic and which consists of thegroup of surfactants designated by the CTFA name of poloxamer 108, 188,217, 237, 238, 288, 338, 407, 101, 105, 122, 123, 124, 181, 182, 183,184, 212, 231, 282, 331, 401, 402, 185, 215, 234, 235, 284, 333, 334,335, and 403.

Fluorine-Containing Surfactant: A surfactant containing one or morefluorine molecules. Some but not necessarily all fluorine containingsurfactants, useful in this invention can be selected from the groupconsisting of: telomer B containing fluorinated surfactants availablefrom Du Pont, Wilmington, Del. under the Trade name of Zonyl (includingZonyl FSA, FSP, FSE, UR, FSJ, FSN, FSO, FSC, FSK, and TBS), thefluorochemical surfactants from 3M Industrial Chemical ProductsDivision, St. Paul, Minn. under the trade name of Fluorad (includingFC-95, FC-98, FC-143, FC-170C, FC-171, FC-430, FC-99, FC-100, FC-120,FC-129, FC-135, FC-431, FC-740), the perfluoroalkylpoly(oxyethylene)surfactants described by Mathis et al. (J Am Chem Soc 106, 6162-6171(1984), incorporated herein by reference), thefluoroalkylthio-etherpoly(oxyethylene) surfactants described bySerratrice et al. (J Chim Phys 87, 1969-1980 (1990), incorporated hereinby reference), the perfluoroalkylated polyhydroxylated surfactants ofZarif et al. (J Am Oil Chem Soc 66, 1515-1523 (1989), incorporatedherein by reference), the fluorosurfactants available from Atochem NorthAmerica, Philadelphia, Pa. under the trade name of Forafac.

Biocompatible Proteins: The group of proteins, regardless of source andwhether obtained by extraction of animal, plant, or microbiologicaltissue or obtained from recombinant biotechnology, which is capable ofperforming its function of stabilizing the colloidal dispersions of theinstant invention in an acceptable manner, without undue toxicity orphysiological or pharmacological effects. Some acceptable biocompatibleproteins can be selected from the group consisting of albumin,alpha-1-antitrypsin, alpha fetoprotein, aminotransferases, amylase,C-reactive protein, carcinoembryonic antigen, ceruloplasmin, complement,creatine phosphokinase, ferritin, fibrinogen, fibrin, transpeptidase,gastrin, serum globulins, hemoglobin, myoglobin, immunoglobulins,lactate dehydrogenase, lipase, lipoproteins, acid phosphatase, alkalinephosphatase, alpha-1-serum protein fraction, alpha-2 serum proteinfraction, beta protein fraction, gamma protein fraction, gamma-glutamyltransferase, and other proteins.

A preferred process for manufacturing the colloidal dispersions of thisdisclosure is comminution. An alternative process for manufacturing iscondensation.

Comminution: The process of forming a colloidal dispersion by mixing theliquid dispersed and continuous phases together and then causing adecrease in size of the particles of the dispersed phase from largeparticles to the size required, using mechanical energy generated bymixing manually, mechanically, or by the action of ultrasound.Appropriate mixing can be achieved in a Microfluidic's Model 110Microfluidizer apparatus, as described in U.S. Pat. No. 4,533,254,incorporated herein by reference. An acceptable alternative is theRannie High Pressure Laboratory Homogeniser, Model Mini-Lab, type 8.30H,or equivalent.

Condensation: The process of forming a colloidal dispersion by startingwith the dispersed phase as a gas, placing it in contact with the liquidcontinuous phase and then causing an increase in size of the particlesof the dispersed phase from a molecular ensemble to the size required,generally by inducing a phase change of the dispersed gas to a liquid bythe action of changes in the system temperature, pressure, or both.

The invention will be better understood by way of the followingexamples:

EXAMPLE 1

The criticality that the low boiling liquid be present as a finelydivided dispersion rather than as a neat liquid, as was described byZiskin et al. (referenced above) was determined by measuring theacoustic backscatter of the two states.

Two solutions were prepared to simulate the administration to anorganism of either a colloidal dispersion of a low boiling liquid or theliquid neat. These were scanned at 5.0 MHz with a Hewlett Packard Model77020 ultrasound scanner and the images obtained recorded on Sony ES VHStape. The analog images from the tape were then converted to a digitalform using the software package Global Lab Image Software (DataTranslation, Marlboro, Mass.). The gray scale intensity within a 4900pixel (70×70 pixel-sized) region-of-interest was then measured beforeand after the injection of the colloidal dispersion of Example 19 or aquantity of neat dodecafluoropentane into a 1000 mL water beakerequilibrated at 37° C.

The measurements were performed on a gray scale of 2 to 254. The imageintensity before injection of a 0.1 mL aliquot of the emulsion ofExample 19 below (containing 3.4 micromoles of dodecafluoropentane) was4.27. The injection of 0.1 mL of this emulsion produced a change ofintensity to 236 five seconds post-injection and 182 fifty-two secondspost-injection.

The same experiment was performed with a 0.2 mL injection of neatdodecafluoropentane. This corresponds to 1111 micromoles ofdodecafluoropentane, over 300-times the quantity in the experimentabove. The image intensity before injection was 4.9; this increased to7.7 five seconds post-injection and 5.0 fifty-two secondspost-injection.

A comparison of these two experiments (intensity/quantity) indicatesthat the colloidal dispersion is 27,000-times more effective atscattering the ultrasound beam than simply an administration of a liquidwhich also undergoes a liquid-to-gas phase transition.

EXAMPLE 2

The selection of an appropriate chemical for the liquid dispersed phaseis governed, in part, by the body temperature of the organism to bestudied by ultrasound. For example, since the body temperature of man is37° C., liquids which undergo a liquid to gas phase transition, i.e.,boil, at or below 37° C. are especially useful in the colloidaldispersions of the invention. In a similar manner, the following tablecan be used as guidance in selecting the liquid dispersed phase,depending on which organism is to be studied:

    ______________________________________                      RECTAL TEMPERATURE    ORGANISM          (degrees Fahrenheit)    ______________________________________    Swine (Sus scrofa)                      101.5-102.5    Sheep (Ovis sp.)  101-103    Rabbit (Oryctolaqus cuniculus)                        102-103.5    Rat (Tattus morvegicus)                       99.5-100.6    Monkey (Macaca mulatta)                      101-102    Mousc (Mus musculus)                       98-101    Goat (Capra hircus)                      101-103    Guinea pig (Cavia porcellus)                      102-104    Hamster (Mesocricetus sp.)                      101-103    Man (Homo sapiens)                       98.6-100.4    Horse (Equus sp.)   101-102.5    Dog (Canin familiaris)                      101-102    Baboon (Papio)     98-100    Cat (Felis catus) 101-102    Cattle (Bos taurus)                      101.5-102.5    Chimpanzee (Pan)   96-100    ______________________________________

EXAMPLE 3

A colloidal dispersion was formed by comminuting, using the method andcriteria of Example 45 below, an organic halide.

Specifically, a 100 mL quantity of a formulation was created containing:poloxamer 488, 2.5% v/v; fluorine-containing surfactant Zonyl FSN 2.5%v/v; sodium perfluorooctanoate, pH 7.0, 0.1% w/v; sodium chloride, 0.9%,w/v; and dodecafluoropentane, 2.0%, v/v. After low shear mixing, thesewere comminuted in the Microfluidizer model 110Y at 4° C. for eightpasses. The milky emulsion was aliquoted into serum vials and sealed.

Within 72 hours, the particle size and size distribution was determinedat 19° C. using the Nicomp model 370 (Nicomp Particle Sizing, SantaBarbara, Calif.). The mean diameter of the Gaussian analysis of theemulsion was 90.1 nm (number weighted) with a standard deviation of 48%.The volume weighted mean diameter was 316 nm.

EXAMPLE 4

The particle size and size distribution were determined at various stepsor under different conditions during the formulation of an emulsion.

A 20 mL quantity of an emulsion was formulated, containing sodiumperfluorooctanoate, pH 7.2,2.5%, w/v, and dodecafluoropentane, 2%, w/v.These ingredients were added to water and the suspension cooled to 4° C.The Emulsiflex-1,000 (Avestin, Inc., Ottawa, Canada) was used to"pre-mix" the solution before final comminution.

Following 20 passes of the solution between two 10 mL syringes, thewhite, milky suspension was placed in the Nicomp 370 to determineparticle size. This pre-mix suspension had a mean particle size (numberweighted) of 452 nm and (Volume weighted) of 2398 nm.

The final emulsion was then formed by comminution through eight passeswith the Emulsiflex-1,000 (Avestin, Inc., Ottawa, Canada) operatingmanually at a pressure of up to 7 MPa. The emulsion particles were muchsmaller, with a number-weighted mean diameter of 201 nm and a volumeweighted mean diameter of 434 nm.

Aseptic filling of the material was achieved by passing the materialthrough a 0.45 micron sterile filter (Gelman Acrodisc, Ann Arbor,Mich.). The final, sterile colloidal dispersion had a number weightedmean diameter of 160 nm.

EXAMPLE 5

The mean particle size measurement of an emulsion immediately aftercomminution is a useful test of the ultimate stability of theformulation. The following emulsions illustrate this point:

A 2%, v/v, dodecafluoropentane emulsion was formulated containing 2%Pluronic P-123 and 2.6% Zonyl FSO, according to the method of Example 19below. The mean particle diameter was 151 nm, with a 35% standarddeviation. This emulsion was stable for at least six weeks, as judged byphysical appearance and particle size.

To the same formulation was added 0.25% sodium perfluorooctonate.Although it was speculated this might further stabilize the formulationbecause this addition reduces interfacial tension, the high anioniccharge density this surfactant could generate at the emulsion interfacemay actually prevent production of small particles. In fact, theimmediate particle size measurements indicated a mean particle size of1060 nm with a standard deviation of 106%. This emulsion degraded in amatter of days.

EXAMPLE 6

The particle size distribution of an emulsion can be measured bycentrifugation. A sample of the emulsion of Example 19 below was placedin the Horiba CAPA-700 Particle Analyzer (Horiba Instruments, Irvine,Calif.). The particle size distribution, based on assuming the particleshave a density of 1.66 g/cu cm, was as follows:

    ______________________________________    Particle Size Range    microns         Volume Percent    ______________________________________    0.0-0.5         12    0.5-1.0         26    1.0-1.5         22    1.5-2.0         15    2.0-2.5         7    2.5-3.0         0    ______________________________________

EXAMPLE 7

The long term stability of the emulsions of the present invention wasdetermined. The emulsion described in Example 19 below was placed at 19°C. and the particle size determined at intervals using the Nicomp 370.The results are contained in the following table:

    ______________________________________    Time       Mean Particle Diameter    (days)     nm    ______________________________________     5         194    13         216    19         245    27         258    33         289    41         283    47         306    61         335    89         305    ______________________________________

This emulsion initially grew rapidly from 194 to 289 nm over the firstmonth. However, since then the growth has largely stopped. Extrapolationof the curve of a graph of diameter vs time supports at least a one yearstability for this emulsion.

EXAMPLE 8

The emulsion of Example 42 below was used to test the imagingcapabilities of these colloidal dispersions administered by variousroutes. An approximately 20 kg mongrel dog was anesthetized with sodiumbarbiturate, and prepared for ultrasound examination according to themethod described in Example 38.

A 0.2 mL/kg intravenous injection produced a strong contrast signal inthe right and left ventricles of the heart within the first minutefollowing the injection. Doses of 0.5 mL/kg produced a strong Dopplersignal in all organs examined, including the vascular system, liver,kidneys, heart, and vessels of the central nervous system.

A 0.5 mL injection either by an intradermal, intracutaneous, orintramuscular route caused local contrast, permitting examination of themusculoskeletal system.

A 1000 mL solution, prepared by diluting 50 mL of the emulsion ofExample 42 into 950 mL of saline, was given by the oral route,effectively providing an intragastric and intraduodenal intraluminaladministration. The lumen of the gastrointestional system was enhanced,providing better visualization of the liver, spleen, and internalreproductive organs.

A 10 mL volume of the emulsion of Example 42 below was administered bythe intracystic route, affording enhanced visualization of the urinarybladder.

The above specific examples could be used to provide useful ultrasoundcontrast with the colloidal dispersions of the present invention byadditional routes of administration. Specifically, the emulsions couldbe given by any of the following routes, among others: intraabdominal,intraarterial, intraarticular, intracapsular, intracervical,intracranial, intraductal, intradural, intralesional, intralocular,intralumbar, intramural, intraocular, intraoperative, intraparietal,intraperitoneal, intrapleural, intrapulmonary, intraspinal,intrathoracic, intratracheal, intratympanic, intrauterine, andintraventricular. Methods for administration by these routes can befound in a standard radiology text, such as "Pharmaceuticals in MedicalImaging," edited by D P Swanson, H M Chilton, J H Thrall. MacMillianPublishing Co., Inc., 1990, which text is incorporated herein byreference.

In addition to the above indicated organs or organ systems studied, onecould study the lungs, breast, prostate, and endocrine systems by knownmeans. The kinds of medical conditions amenable to study with the agentsof the present invention are numerous. They include metabolic,traumatic, congenital, neoplastic, or infectious diseases. A descriptionof the use of ultrasound imaging in these conditions can be found in thetext "Diagnostic Ultrasound," edited by C M Rumack, S R Wilson, J WCharboneau, Mosby Year Book, Boston, 1991, incorporated herein byreference.

EXAMPLE 9

The colloidal dispersions of the present invention can produce acontrast effect in the ultrasound signal at concentrations ranging from0.00001% w/v to 166% w/v.

If a 1% emulsion (such as the emulsion of Example 42) is dilutedten-fold (by adding one mL to nine mL of buffer) and a 0.1 mL aliquotadded to 1000 mL water at 37° C. and the ultrasound intensity measured,there is a substantial increase in the backscatter. Specifically, thesignal intensity, measured with the system described in Example 1,increases from 2.7 to 9.8 within the first minute following the aboveaddition. At a greater dilution, the backscatter is indistinguishablefrom background. Thus, the lower limit for the concentration of thedispersed phase material is 0.00001%.

If 5 mL of dodecafluoropentane is added to 5 mL of water containing thesurfactant mixture described in Example 25 below, and the suspensioncomminuted for 5 minutes by the method of Example 4, a 166% w/v emulsionis formed. This can be immediately administered, for example orally, toan organism to afford excellent ultrasound contrast. This amountrepresents a high end to the concentration of the dispersed phasematerial because higher concentrations produce formulations which tendto be unstable.

EXAMPLE 10

Proteins can be used to stabilize the colloidal dispersions of thepresent invention. Using high-intensity ultrasound, one can synthesizeaqueous suspensions of proteinaceous microspheres filled with nonaqueousliquids (i.e., microcapsules). These are distinct from the ultrasoundcontrast agents of U.S. Pat. Nos. 4,718,433 and 4,774,958, which containonly gases, and follow the methods described by Suslick and Grinstaff(Suslick K S, Grinstaff M W:Protein microencapsulation of nonaqueousliquids. J Amer Chem Soc 112:7807-7809, 1990). This reference describesonly the use of high boiling nonaqueous liquids (which are unsuitable asultrasound contrast agents) and fails to disclose the use of either lowboiling liquids in general, or organic halides, in particular, as thenonaqueous liquids.

Proteinaceous microspheres can be synthesized with a high intensityultrasound probe (Heat Systems, W375, 20 kHz, 0.5 in. Ti horn) fromhuman serum albumin or hemoglobin. Typically, 5% pentane or 3% diethylether and 5% albumin are irradiated for three minutes at an acousticpower of about 150 W/sq cm, at 23° C. and a pH of 7.0. The resultingdispersion has a Gaussian distribution and a mean particle diameter ofabout 2.3 microns. They maintain their particle size for up to twomonths at 4° C.

In addition to albumin or hemoglobin, the following proteins can beused: alpha-1-antitrypsin, alpha fetoprotein, aminotransferases,amylase, C-reactive protein, carcinoembryonic antigen, ceruloplasmin,complement, creatine phosphokinase, ferritin, fibrinogen, fibrin,transpeptidase, gastrin, serum globulins, myoglobin, immunoglobulins,lactate dehydrogenase, lipase, lipoproteins, acid phosphatase, alkalinephosphatase, alpha-1-serum protein fraction, alpha-2-serum proteinfraction, beta protein fraction, gamma protein fraction, gamma-glutamyltransferase.

In addition to pentane or diethyl ether, other aliphatic hydrocarbons,organic halides, and ethers can be used as described above for pentane.

EXAMPLE 11

The relationship of the size of the particles of the colloidaldispersion as an emulsion or microemulsion and the size of themicrobubbles formed upon phase shift can be determined.

An aliquot of the emulsion of Example 27 below was placed in the Nicomp370, operating at 19° C. and the mean particle size of the liquidemulsion was determined to be 231.7 nm. The temperature control of theinstrument was adjusted to 37° C. and after temperature equilibration,which took about five minutes, the particle size was redetermined. Themicrobubble dispersion formed had a mean particle size of 1701.5 nm, anincrease in size of 7.34-fold.

One can also calculate the expected change in dispersion size if oneknows the relative densities of the dispersed liquid as a gas andliquid. For example, the Gas Data Book, by W Braker and A Mossman,Matheson, contains such data. Examining octafluorocyclobutane, one findsthat 1 L of the liquid yields 188 L of gas at a pressure of 760 mm Hgand 15° C. Since the volume of a sphere is related to the diameter of asphere by the cubic root of the volume, the phase transition for anoctafluorobutane emulsion particle will cause a 5.7-fold increase indiameter.

EXAMPLE 12

The safety of the emulsions of the present invention is dramaticallydemonstrated in the mini-pig. Albunex brand ultrasound contrast agent,under development and the subject of U.S. Pat. Nos. 4,718,433 and4,774,958, shows grave hemodynamic effects in the pig (Ostensen J, HedeR, Myreng Y, Ege T, Holtz E.) Intravenous injection of Albunexmicrospheres causes thromboxane mediated pulmonary hypertension in pigs,but not in monkeys or rabbits. Acta Physiol Scand 144:307-315, 1992). Atdoses as low as 0.001-0.05 mL per kg hypotension results. One pig diedafter a slow infusion of 0.05 mL per kg.

An experiment was performed in a 30 kg mini-pig under halothaneanesthesia, using the protocol of the above reference. The results arecontained in the following table:

    ______________________________________    Dose, mL/kg              Cumulative Dose, mL/kg                               Hemodynamic Effect    ______________________________________    0.01      0.01             None    0.02      0.03             None    0.05      0.08             None    0.10      0.18             None    0.20      0.38             None    0.30      0.68             None    0.40      1.08             None    0.50      1.58             None    0.60      2.18             None    0.60      2.78             None    0.80      3.58             None    0.30      3.88             None    2.00      5.88             labored                               breathing    ______________________________________

All doses provided good cardiac contrast. The doses above 0.4 mL/kgprovided Doppler enhancement of the liver as well.

In conclusion, injections of an emulsion of the present invention at40-times the lethal dose of albumin microspheres in the mini-pig hadminimal, transient effects. The threshold dose for an effect withAlbunex is 0.001 mL per kg of the albumin microspheres or 2000-timesbelow the threshold dose for an effect of the colloidal dispersions ofthe present invention.

EXAMPLE 13

The selection of amphiphilic materials with the properhydrophilic-lipophilic balance (HLB) number for the selected dispersedphase is important for the stability of the colloidal dispersion. Oneway to determine the HLB number is to measure the interfacial tension ofvarious surfactant mixtures. (A good general review of the HLB methodcan be found in: Emulsions: Theory and Practise, Paul Becher, Robert E.Krieger Publishing Company, Malabar, Fla., 1965, pp.232-252,incorporated herein by reference).

Mixtures of Pluronic P-123 and Pluronic F-127 were formed, yielding a 1%solution, v/v, with graded HLB numbers and the interfacial tension (IFT)of the solutions against dodecafluoropentane determined at 4° C., usinga Kruss Drop Volume Tensiometer DVT-10, Kruss USA, Charlotte, N.C. Theresults are contained in the following table:

    ______________________________________    RELATIONSHIP BETWEEN HLB AND INTERFACIAL TENSION    P-123   F-127        HLB    IFT (dynes/cm)    ______________________________________    1.00    0.00          8     27.07    0.86    0.14         10     23.94    0.75    0.25         12     23.58    0.60    0.40         14     22.48    0.50    0.50         15     22.80    0.40    0.60         16     23.16    0.25    0.75         19     23.61    0.00    1.00         22     26.36    ______________________________________

The above data, when graphed, indicate an HLB for dodecafluoropentane ofabout 14. The use of amphiphilic materials, such as anionic, nonionic,cationic, or zwitterionic surfactants with an HLB number of 14 willprovide the greatest stability for emulsions of the above liquiddispersed phase.

EXAMPLE 14

The interfacial tension between the liquid dispersed phase and theliquid continuous phase can be used to develop formulations, since thisproperty has a significant influence on the stability of the colloidaldispersion.

The Ostwald ripening theory predicts a strong dependence of particlesize stability on interfacial tension (reviewed by Kabalnov A S,Shchukin E D; Ostwald ripening theory: Applications to fluorocarbonemulsion stability, Advances in Colloid and Interface Science, 38:69-97,1992, incorporated herein by reference). The theory predicts stabilityand interfacial tension are inversely proportionate to each other. Forexample, if one can add amphiphilic materials which provide a five-foldlowering of interfacial tension, one will obtain a five-fold increase instability.

Interfacial tensions of various amphiphilic materials in aqueoussolutions (all expressed as v/v solutions) against dodecafluoropentanewere measured at 4° C. and emulsions created from each formulation, asdescribed in Example 13.

Pluronic P-123, 1%, and dodecafluoropentane had an interfacial tensionof 27.1 dynes/cm and did not form a stable emulsion.

Pluronic F-127, 1%, and dodecafluoropentane had an interfacial tensionof 26.4 dynes/cm and did not form a stable emulsion.

Zonyl FSO, 1%, and dodecafluoropentane had an interfacial tension of 5.8dynes/cm and formed a stable emulsion.

Pluronic P-123, 0.33%, Pluronic F-127, 0.33%, and Zonyl FSN, 0.33%, anddodecafluoropentane had an interfacial tension of 14.1 dynes/cm and didform a stable emulsion.

Pluronic P-123, 1%, Zonyl FSO, 1.0%, sodium chloride, 1%, and sodiumperfluorooctanoate, 0.5%, and dodecafluoropentane had an interfacialtension of 2.71 dynes/cm and formed a stable emulsion.

Thus, amphiphilic materials with interfacial tensions below 26 dynes/cmwere required to form stable emulsions. Related findings would beobtained with other organic halides or with aliphatic hydrocarbons orethers.

EXAMPLE 15

The viscosity of the liquid continuous phase can be used to developformulations, since this property has a significant influence on thestability of the colloidal dispersion.

The Ostwald ripening theory predicts a strong dependence on particlesize stability and viscosity (see Kabalnov A S, et al. in Example 14).The theory predicts stability and viscosity are directly proportionateto each other. For example, if one can add viscogens (viscosityenhancing agents) which provide a five-fold increase in viscosity, onewill, in general, obtain a five-fold increase in stability.

Examples of viscogens include, but are not limited to,carboxymethylcellulose, sorbitol, iohexol, other iodinated x-raycontrast materials, dextrose, polyethylene glycols. The emulsion ofExample 38 below was prepared with or without 5% polyethylene glycol(PEG) 200, which produced a viscosity of 1.1 cP, and stability noted.The emulsion containing 5% PEG 200 had greater stability.

EXAMPLE 16

The ultrasound backscatter from dispersions of the emulsions of Examples44 and 18 below were measured with a Hewlett Packard Model 77020ultrasound scanner to determine the relative potency of the phase shiftcolloids of the present invention, which are liquid-liquid emulsiondispersions at room temperature but which become microbubbles followingadministration with either stable emulsions, as described by Long andothers (U.S. Pat. Nos. 7,767,610, 4,987,154, and JP 2196730), Davis andothers (EP 245019), and JP Patent 1609986 and JP 63060943), or with trueair microbubbles, as described in EP 467031, EP 458745, WO 9115244, U.S.Pat. Nos. 5,088,499, 5,123,414, U.S. Pat. No. 4,844,882, U.S. Pat. No.4,832,941, U.S. Pat. No. 4,466,442, and U.S. Pat. No. 4,276,885, each ofwhich is incorporated herein by reference.

The air microbubbles were created by the following procedure. Introduce0.5 mL of air into a 10 mL syringe and 10 mL of a 1.0%, v/v, solution ofPluronic F-68 into another 10 mL syringe, which is connected to thefirst syringe by a three-way stopcock. Pass the liquid and air back andforth between the two syringes rapidly. After about five passes the airand liquid have mixed and the solution has a milky, white appearance.Continue mixing for a total of 20 passes. A 1.0 mL sample of the gasdispersion added to 250 mL of water gave an ultrasound image with anintensity similar to hepatic tissue (4+ strength). Surprisingly, theintensity of the ultrasound backscatter produced by the air microbubblesdecreased rapidly, so that within five minutes the backscatter hadreturned to base line. This lack of persistence limits the diagnosticutility of air microbubbles.

On the other hand, 1.0 to 10.0 mL of a perfluorohexane emulsion in 250mL of water at 37° C. yielded an ultrasound image similar to flowingblood (0-1+ strength), indicating that these formulations produceultrasound contrast only at extremely high dosages, which limit theirgeneral utility.

A 1.0 mL sample of the dodecafluoropentane emulsion diluted in 250 mL of37° C. water yielded an ultrasound image with the intensity of themicrobubble solutions (4+ strength).

Parenthetically, all three experimental solutions were visually cloudysolutions of nearly equal apparent turbidity. These experimentsdemonstrate that the ultrasound contrast agents of the present inventionshow greater persistence and/or potency then the prior art ultrasoundcontrast agents to a diagnostically useful extent.

EXAMPLE 17

A 1.0 mL sample of the contrast agent of Example 19 was withdrawn from avial with a 1.0 mL syringe equipped with a 21-gauge needle andapproximately 0.2 mL placed on a glass slide. A glass cover slip wasplaced over the liquid and the sample placed on the stage of a lightmicroscope equipped with an eye piece micrometer, atemperature-controlled chamber, a 35-mm camera, and a Panasonic videocamera.

The emulsion was examined under oil-immersion at 20° C. At thistemperature the emulsion consisted of 0.2-0.3 micron particles whichwere undergoing rapid Brownian motion.

The temperature control was changed to 37° C. and the emulsion observedand images recorded. As the temperature rose the particles wouldindividually suddenly grow in size until at 37° C. the emulsion hadbecome a collection of 1-3 micron bubbles. The bubbles, in distinctionto the liquid emulsion, were easily deformable. They did not, however,appear to coalesce. After 40 minutes of experimentation the microbubbleensemble remained intact and stable.

EXAMPLE 18

The criticality that some portion of the liquid dispersed phase undergoa liquid to gas phase transition at the body temperature of the organismto be imaged, in this case using an example temperature of 37° C., tothe utility as an ultrasound contrast agent was tested by subjecting aseries of emulsions, each with different liquid dispersed phases, toultrasound imaging at 37° C.

The following emulsions were formulated or obtained from sources and 1.0mL aliquots placed in 1000 mL of water at 37° C. The emulsion formedwith 1-iodoperfluorooctane was formulated according to the methodsdisclosed by Long and others (U.S. Pat. Nos. 4,767,610, 4,987,154 and JP2196730). The emulsion with perfluorodecalin was formulated according tothe disclosures of JP Patent 1609986 and JP 63060943. The emulsion withtriolean was formulated according to methods disclosed by Davis andothers (EP 245019). The contents of each of these patents are herebyincorporated by reference. Ultrasound images were obtained of thesolution before and after the addition and the results expressed as apercentage of enhancement times the length of time over whichenhancement was observed.

    __________________________________________________________________________                            Boiling                                 Enhancement    Dispersed               Point                                 Percent-Minutes    Phase     Amphiphilic Material/Class D.P.                            (°C.)                                 X1000    __________________________________________________________________________    Decaflurobutane              Octadecylamine HCl/Cationic                              -5.8                                 625    Dodecafluropentane              Poloxamer-Zonyl/Nonionic                            29                              740    Perfluorohexane              Dodecylsulfate/Anionic                              59 178    Perfluorcoctane              Poloxamer-Zonyl/Nonionic                            98                              24    Perfluorodecalin              Poloxamer-Phospholipid-Oleate                              141                                 8              /Mixed    1-Iodoperfluorooctane              Phospholipid/Zwitterionic                              160                                 6    Triolean  Phospholipid/Zwitterionic                              235                                 0.2    Saline    Not Applicable                            Shaken                                 0.006    __________________________________________________________________________

As indicated above, the preferred formulations are the emulsions whichundergo a complete phase shift at or below 37° C. However, the highvapor pressure liquids perfluorohexane and perfluorooctane which havevapor pressures at ambient temperature above 20 Torr, provided usefulcontrast and show improved contrast when compared to agitated saline orperfluorodecalin which has a vapor pressure at ambient temperature below20 Torr.

EXAMPLE 19

The ultrasound contrast agents of the present invention can be made withthe following equipment and steps: Microfluidizer, Model 110Y,Interaction chamber pressure 14,000 PSI; Pressure vessels, 316 steel, 5L and 12 L sizes; Filters, cellulose acetate, 0.22 micron; Filterholders, 142 mm. The following solutions were made: 25% (w/v) sorbitol,12 L; 2.5% w/v sodium perfluorooctanoate (PCR, Inc., Gainsville, Fla.);60 g Pluronic P-123, 60 g Zonyl FSO, 7 mL 2.5% sodiumperfluoro-octanoate solution, 1 L, sonicate to aid dissolution (stocksurfactant solution). The Microfluidizer was primed with the sorbitolsolution. The interaction chamber, tubing, and cooling coil are coveredwith chipped ice during the comminution process. To a 5 L pressurevessel with stir bar in an ice bath add sequentially: 500 mL sorbitolsolution; 500 mL stock surfactant solution; 800 mL water; 200 gdodecafluoropentane. Pressurize vessel to 10 PSI with nitrogen for 45min. Pass the suspension through the Microfluidizer for 45 min at 14,000PSI. Transfer the emulsion to a vessel containing 8 L of 25% sorbitol at4° C. and mix well. Transfer the emulsion to 100 mL vials using positivepressure, passing the material through a 0.22 micron filter in theprocess. Cap and seal the vials. The amphiphilic materials of thisExample, including fluorine-containing surfactants andpolyoxypropylene-polyoxyethylene glycol nonionic block co-polymers,produce a formulation with acceptable stability.

EXAMPLE 20

A 0.4 ml portion of n-pentane (Aldrich Chemical, Milwaukee, Wis.) wasadded to 2.0 mL of water at 4° C. Two clear separated phases resulted.NaCl was added (0.4 mL of a 10% w/v solution) to make a total of 2.8 mL.Approximately 135 mg of phosphatidyl lecithin (Sigma Chemical, St.Louis, Mo.) was added with stirring and the resulting slurry mixed byvigorous vortex agitation. The milky white solution separated into twophases within 5 min. upon standing. Ethanol was added in 0.1 mLincrements with mixing to a total of 1.74 mL. There was no change in theappearance of the two-phase mixture. The formulation of this Exampleshowed good in vitro ultrasound backscatter characteristics anddemonstrates the use of aliphatic hydrocarbons having six or fewercarbon atoms and 17 total atoms.

EXAMPLE 21

A milky suspension was formed by adding together 1.80 mL water, 0.2 mL10% NaCl, 0.1 mL ethanol, and 100 mg lecithin. A 0.1 mL portion ofdodecafluoropentane (PCR, Gainsville, Fla.) was added and followingmixing two phases were obtained. A 0.1 mL portion of n-pentane was addedand then 0.2 mL dodecafluoropentane aliquots were added to bring thetotal dodecafluoropentane to 20% v/v. The resulting suspension was mixedand three phases obtained, two milky phases and a small clear phase.Additional NaCl was added to bring the solution to 7% and a 1 mL aliquotof ethanol added with no change in the character of suspension. Theformulation of this Example showed good in vitro ultrasound backscattercharacteristics and demonstrates the use of mixtures of a hydrocarbonand a fluorocarbon.

EXAMPLE 22

To a 2.0 ml portion of dodecafluoropentane was added 330 mg of lecithin.Following mixing, 1.0 mL of water was added and the suspension furthermixed. A milky colloidal dispersion was formed. A milky colloidaldispersion was formed, demonstrating the use of a single surfactant asthe amphiphilic material, in this case a naturally-occurringzwitterionic surfactant. Useful contrast agents are formed by replacingthe portion of dodecafluoropentane in the formulation with an ether,such as, methyl ether, diethyl ether, or vinyl ether.

EXAMPLE 23

A 0.46 g portion of sodium dodecylsulfate (SDS) was added to 0.72 mLwater and 8.00 mL dodecane. A 1.47 mL aliquot of pentanol was slowlyadded. Initially the suspension contained white, "filamentous" SDS in aclear fluid. A 1.0 mL addition of pentanol and gentle mixing lead to asubstantial dissolution of the SDS. A 0.5 mL addition of pentanol withmixing lead over 10-15 min at room temperature to a clear, monophasicmicroemulsion. This formulation produced rather poor acousticbackscatter, demonstrating that a colloidal dispersion containing aliquid dispersed phase with an ambient temperature vapor pressure ofless than 20 mm Hg, here exemplified by dodecane, is unsuitable as anultrasound contrast agent.

EXAMPLE 24

The composition of the water, pentanol, dodecane, sodium dodecylsulfatemicroemulsion of Example 23 was varied to determine the compositionalboundaries of the microemulsion. The following mixtures were prepared atroom temperature and the appearance following 30 min. of stirring wasnoted: Volume of Addition (mL)

    __________________________________________________________________________    EXPERIMENT           WATER                PENTANOL                      DODECANE                             SDS APPEARANCE    __________________________________________________________________________    5-1    1.00 1.00  1.00   372 mg                                 Clear    5-2    1.10 1.00  1.00   372 mg                                 Clear    5-3    1.20 1.00  1.00   372 mg                                 Clear    5-4    1.30 1.00  1.00   372 mg                                 Clear    5-5    1.50 1.00  1.00   372 mg                                 Milky    5-6    1.50 1.10  1.00   372 mg                                 Milky    5-7    1.50 1.30  1.00   372 mg                                 Milky    5-8    1.50 1.50  1.00   372 mg                                 Slt. Milky    5-9    1.50 1.60  1.00   372 mg                                 Clear, Bluish Cast    __________________________________________________________________________

The 5-9 microemulsion became milky upon heating (greater than about 45°C.) and became clear, with a bluish cast, again upon cooling to roomtemperature. This reversible change in appearance could be repeatedthrough at least six temperature shift cycles.

EXAMPLE 25

A 0.51 mL portion of octyl amine (Sigma Chemical Corp., St. Louis, Mo.)was added to 1.0 mL of water to form a clear solution. A 1.0 mL portionof octane was added and the clear solution became milky. A 0.49 mLportion of octanoic acid was added and the solution became a gel. A 0.17mL aliquot of a 3.6M KOH solution dissolved the gel to produce a clearmicroemulsion. Five additions of water in 0.1 mL aliquots with mixingcontinued to yield a clear microemulsion. The sixth addition convertedthe clear emulsion to a milky colloidal dispersion. This Exampledemonstrates the formulation of an aliphatic hydrocarbon-containingemulsion with amphiphilic material comprising cationic surfactants.

EXAMPLE 26

A 1.0 mL portion of dodecafluoroheptanol (PCR) was added to 1.0 mL ofdodecafluoropentane to form a clear, homogenous solution. The samequantity of octafluoropentanol in dodecafluoropentane yielded two clear,non-mixing phases. The addition of 2.0 to 4.0 mL water to thedodecafluoroheptanol-dodecafluoropentane yielded two non-mixing phases.Upon cooling to 4° C. the two clear phases changed to three clearphases.

EXAMPLE 27

A solution of 10% (v/v) Fluorad FC-430 (3M Chemical, St. Paul, Minn.) inwater was prepared by adding 10 mL FC-430 to 100 mL water at roomtemperature and mixing. To 5 mL of this solution 1.0 mLdodecafluoropentane and 1.0 mL octafluoropentanol was added to yield anemulsion.

EXAMPLE 28

A 2.0 ml portion of 10% v/v FC-430 solution was added to 2.0 mLdodqcafluropentane and two phases resulted. The addition of 0.3 mLdodecafluoroheptanol yielded a milky, white emulsion.

EXAMPLE 29

A 1 mL portion of 1.26M 2-amino-2-methyl-1-propanol (AMP)perfluorooctanoate was added to 1.0 mL of dodecafluoropentane, and 1 mLof 25% Pluronic F68 to yield two phases of milky liquid. A 0.05 mLaddition of dodecafluoroheptanol yielded a single phase colloidaldispersion.

EXAMPLE 30

A 2.0 mL portion of a 15% (v/v) Pluronic F68 solution was addedsequentially to 2.0 mL dodecafluoropentane and 0.2 mLdodecafluoroheptanol on ice. The mixture was taken up in a 5 mL glasssyringe connected to a three-way stopcock and a second 5 mL glasssyringe and forcefully passed back and forth between the syringes toyield a thick white emulsion.

EXAMPLE 31

The following mixture was formed by sequential addition at 4° C.: 2.0 mL15% Pluronic F68, 2.0 mL dodecafluoropentane, 2.0 mL 0.2M AMPperfluoroctanoate, 0.1 mL dodecafluoroheptanol. The mixture was taken upin a 5 mL glass syringe connected to a three-way stopcock and a second 5mL glass syringe and forcefully passed back and forth between thesyringes to yield a thick white emulsion.

EXAMPLE 32

The following mixture was formed by sequential addition at 4° C.: 2.0 ml15% Pluronic F68, 0.42 g D-sorbitol (Sigma) dissolved in 0.5 mL H₂ O,0.2 mL dodecafluoroheptanol, and 2.0 mL dodecafluoropentane. The mixturewas taken up in a 5 mL glass syringe connected to a three-way stopcockand a second 5 mL glass syringe and forcefully passed back and forthbetween the syringes to yield a thick white emulsion.

EXAMPLE 33

The following mixture was formed by sequential addition at 4° C.: 2.0 mLof 15% (v/v) Pluronic F-68, 0.40 mL 0.1M Tris(hydroxymethyl) aminomethane (Tris) perfluorooctanoate, pH 7.2, 2.0 mL dodecafluoropentane.The mixture was taken up in a 5 mL glass syringe connected to athree-way stopcock and a second 5 mL glass syringe and forcefully passedback and forth between the syringes to yield a white colloidaldispersion.

EXAMPLE 34

The following mixture was formed by sequential addition at 4° C.: 60 mL25% Pluronic F68, 24 mL 1,1,7-H-dodecafluoroheptanol, 75.8 gdodecafluoropentane. The mixture was comminuted by batchwise mixingusing 30 cc syringes, a three-way stopcock and 40 manual passages. Themixture was sequentially diluted 1:10 twice with a solution composed of8.0 mL 25% Pluronic F68, 2.0 mL 50% D-sorbitol, 1.0 mL pH 7.2, 0.1M Trisperfluorooctanoate and further comminuted by syringe passage. Thisformulation was administered to mice, weighing 20-30 g, intravenously bytail vein injection and observed for seven days. The results arecontained in the following table:

    ______________________________________    DOSAGE (mL/kg)      OBSERVATIONS    ______________________________________    20                  Survival    25                  Morbid but survival    30                  Morbid but survival    40                  No Survival    ______________________________________

This biocompatible colloidal dispersion was stable for at least twoweeks after formulation.

EXAMPLE 35

The following formulation was prepared: 1.0 mL 25% polyethylene glycol3550, 1.0 mL 50% sorbitol, 3.0 mL 15% (w/v) Pluronic F-68, 3.0 mL 20%(w/v) Fluorosurfactant FC 430, 0.4 mL 0.1M Tris perfluorooctanoate and1.0% (v/v) dodecafluoropentane. The mixture was comminuted in a waterbath sonicator by the application of acoustic energy at 4° C. for 10 minto yield a milky colloidal dispersion.

EXAMPLE 36

A series of solutions of aqueous media, each containing differentproportions of amphiphilic materials, were formed and tested as thebasis for a formulation.

Solution A: A clear solution containing 6.0 mL of a 25% solution ofPluronic F-68, 6.0 mL of a 50% solution of PEG 3350, 0.60 mL 0.1M Trisperfluorooctanoate, and 2.4 mL H₂ O.

Solution B: A clear solution containing 1.18 mL of a 25% solution ofPluronic F68, 6.0 mL of a 50% solution of PEG 3350, 0.12 mL Trisperfluorooctanoate and 7.7 mL H₂ O.

Solution C: A turbid solution, containing a gelled precipitate, wasobtained by mixing 6.0 mL of 50% PEG 3350, 0.75 mL Trisperfluorooctanoate and 1.5 mL H₂ O. This solution is not biocompatiblefor intravascular administration but is biocompatible for oral,intraperitoneal, rectal or intrauterine administration.

Solution D: A clear solution was obtained by mixing 6.0 mL 25% (w/v)Pluronic F-68, 6.0 mL 50% (w/v) PEG 3350, 0.6 mL 0.1M Trisperfluorooctanoate and 2.4 mL H₂ O.

Solution E: A clear solution was obtained by mixing 6.0 mL 50% (w/v) PEG3350, 7.5 mL 20% (w/v) FC-430, 0.75 mL Tris perfluoroctanoate and 0.75mL H₂ O.

Solution F: A clear solution was obtained by mixing 1.8 mL 25% (w/v)Pluronic F-68, 6.0 mL 50% (w/v) PEG 3350, 0.12 mL 0.1M Trisperfluorooctanoate, and 7.7 mL H₂ O.

Solution G: A clear solution, containing a tiny precipitate was formedby mixing a 3.0 mL Pluronic F-68 3.75 mL (w/v) FC-430, 6.0 mL PEG 3350,0.68 mL Tris perfluorooctanoate, and 1.57 mL H₂ O.

To 7.0 mL of solutions A-G a 0.14 mL portion of dodecafluoropentane wasadded at 4° C. The colloidal dispersions were created by 40 passesbetween two syringes using a three-way stopcock.

Formulation D was administered to mice via tail vein injection and had aLD50 of 20 ml/kg. Formulations F and G were toxic at 10 ml/kg.

EXAMPLE 37

An emulsion was formulated by mixing 45 mL of 20% PEG 3350, 237 mgPluoronic F68, 0.225 mL Fluorad FC-171, 2.25 mL 0.1M Trisperfluorooctanoate, and 10% (v/v) dodecafluoropentane. This wascomminuted by mixing in a two-syringe, three-way stopcock apparatus.

This formulation was biocompatible in a test of hemolysis. Whole bloodwas collected from a rat by intracardiac puncture (2.0 mL) in aEDTA-containing evacuated collection tube. A 0.10 mL aliquot of bloodwas added to a 0.20 mL aliquot of the above formulation to simulate thepeak blood level obtained following an intravenous dosage of 100 mL/kg.The blood was mixed with the formulation for two minutes and the samplecentrifuged. The supernatant was clear, the pellet deep red, indicatingno hemolysis even at this extremely large dosage.

This formulation was also biocompatible in a test of acute toxicity bycausing only minor, labored breathing in mice after intravenuousadministration at 20 mL/kg.

EXAMPLE 38

A formulation containing dodecafluoropentane and amphiphilic materialsin an aqueous media was tested for biocompatibility and utility as anultrasound contrast agent. A stock solution of 90 mL of 20% PEG 3350,474 mg of Pluronic F-68, 0.45 mL Flurorad FC-171, and 4.5 mL 0.1M Trisperfluorooctanoate was mixed and yielded a clear solution. To 9.0 mL ofabove was added 0.18 mL of dodecafluoropentane. A colloidal dispersionwas formed by comminution between two 5 mL syringes.

An echocardiology study was performed in a 32 kg dog according to themodel described by Keller M W, Feinstein S B, Watson D D: Successfulleft ventricular opacification following peripheral venous injection ofsonicated contrast: An experimental evaluation. Am Heart J 114: 570d(1987), incorporated herein by reference. Eleven administrations of theabove formulation were given intravenously at doses of 0.05 to 0.75mL/kg. The 0.05 mL/kg dose gave only slight contrast enhancement of theright and left ventricles immediately following injection. All dosesbetween 0.10 and 0.75 mL/kg gave diagnostically useful enhancement ofthe ventricular chambers. The injections had a minimal effect onhemodynamic parameters.

A 10% dodecafluoropentane emulsion was formed in the above formulatedaqueous media and the contrast enhancement produced compared to the 2%formulation. At doses of 0.20 and 0.25 mL/kg this formulation producedintense cardiac chamber opacification following intravenousadministration with minimal hemodynamic changes.

EXAMPLE 39

An emulsion containing a high density, high viscosity biocompatibleaqueous medium as the continuous phase was formulated. It contained 0.06mL of 15% Pluronic F68, 0.06 mL Zonyl FSO-100, 0.12 mL of 5% ZonylFSN-100, 0.146 mL of 0.1M Tris perflurooctanoate, pH 7.2, 4.47 mL of 76%w/v iohexol (Omnipaque 350, Sterling Winthrop, N.Y.), and 0.6 mL ofdodecafluoropentane. A stable formulation was formed followingcomminution by 2-syringe mixing. Other high density iodinated x-raycontrast materials could be substituted for iohexol. Use of water aloneas the continuous phase medium yielded contrast agents which settledrapidly following formulation in the bottle. This example demonstratesthe utility of a high density, high viscosity biocompatible aqueousmedium as the continuous phase.

EXAMPLE 40

A series of polyoxypropylene-polyoxyethylene glycol nonionic blockcopolymers were tested for their ability to act as amphiphilic materialsin stabilizing the formulations of dodecafluoropentane liquid-liquidemulsions. The following solutions were formed:

A-1.9 mL of 25% Pluronic F-68 and 0.04 mL dodecafluoropentane

B-1.9 mL of Pluronic L-121 and 0.04 ml dodecafluoropentane

C-1.9 mL of Pluronic L-122 and 0.04 mL dodecafluoropentane

D-1.9 mL of Pluronic L-121 and 0.04 mL dodecafluoropentane

E-1.9 mL of Pluronic L-101 and 0.04 mL dodecafluoropentane

F-1.9 mL of Pluronic L-92 and 0.04 mL dodecafluoropentane

G-1.9 mL of Pluronic L-81 and 0.04 mL dodecafluoropentane

H-1.9 mL of Pluronic P-123 and 0.04 mL dodecafluoropentane

The above solutions were placed in sealed glass tubes and vortex mixedat 4° C. for 10 min. The size and number of the disperseddodecafluoropentane phase particles was accessed visually. Solution Hyielded the smallest particles.

EXAMPLE 41

The relative hydrophilic-lipophilic balance (HLB) is a method ofoptimizing a nonionic surfactant solution to achieve greatest stability.It is described in detail in Emulsions: Theory and Practice, PaulBecher, 1965, Robert E. Krieger Publishing Company Malabar, Fla., andreferences contained therein, and is incorporated here by reference.Solutions of Pluronic L61 (HLB 3.0) and F68 (HLB 29) were mixed toachieve intermediate HLB values by the following formula:

    HLB=f.sub.L61 {HLB of L61}+f.sub.f68 {HLB of F68}

The actual solutions, the calculated HLB values, and the stability ofthe final formulation (a 2% v/v emulsion of dodecafluorohexane) arecontained in the following table:

    ______________________________________    PLURONIC L61              PLURONIC F68                          RELATIVE HLB                                      STABILITY    ______________________________________    9.6mL     0.4mL       4           0    8.8       1.2         6           +++    8.1       1.9         8           +++    7.3       2.7         10          +    6/5       3.5         12          0    5.8       4.2         14          0    5.0       5.0         16          0    4.2       5.8         18          0    ______________________________________     0 = no stability;     + = some stability;     +++ = greatest stability

The relative HLB for perfluorohexane established by this work is 6-8.The greatest stability of perfluorohexane emulsions will be achieved byusing amphiliphic materials with relative HLB values of 6-8, regardlessof their chemical structure.

EXAMPLE 42

A large scale formulation of ultrasound contrast agents of the presentinvention can involve the following equipment and steps: Microfluidizer,Model 110Y, Interaction chamber pressure 14,000 PSI; Pressure vessels,316 steel, 5 L and 12 L sizes; Filters, cellulose acetate, 0.22 micron;Filter holders, 142 mm. The following solutions were made: 25% (w/v)sorbitol, 12 L; 60 g Pluronic P-123, 60 g Zonyl FSO, 1 L, sonicate toaid dissolution (stock surfactant solution). The Microfluidizer wasprimed with the sorbitol solution. The interaction chamber, tubing, andcooling coil are covered with chipped ice during the comminutionprocess. To a 5 L pressure vessel with stir bar in an ice bath addsequentially: 500 mL sorbitol solution; 500 mL stock surfactantsolution; 800 mL water; 200 g dodecafluoropentane. Pressurize vessel to10 PSI with nitrogen for 45 min. Pass the suspension through theMicrofluidizer for 45 min at 14,000 PSI. Transfer the emulsion to avessel containing 8 L of 25% sorbitol at 4° C. and mix well. Transferthe emulsion to 100 mL vials using positive pressure, passing thematerial through a 0.22 micron filter in the process. Cap and seal thevials.

EXAMPLE 43

A formulation of the present invention involves the following equipmentand steps: Microfluidizer, Model 110Y, Interaction chamber pressure14,000 PSI; Pressure vessels, 316 steel, 5 L and 12 L sizes; Filters,cellulose acetate, 0.22 micron; Filter holders, 142 mm. The followingsolutions were made: 62.5% (w/v) sorbitol, 10 L; 41.75 g Pluronic P-123,41.75 g Zonyl FSO, 2.5 L, sonicate to aid dissolution (stock surfactantsolution). The Microfluidizer was primed with the sorbitol solution. Theinteraction chamber, tubing, and cooling coil are covered with chippedice during the comminution process. To a 5 L pressure vessel with stirbar in an ice bath add sequentially: 1800 mL stock surfactant solution;200 g dodecafluoropentane. Pressurize vessel to 10 PSI with nitrogen for45 min while stirring. Pass the suspension through the Microfluidizerfor 30 min at 5,000 PSI and for 60 min at 14,000 PSI. Transfer theemulsion to a vessel containing 8 L of 62.5% sorbitol at 4° C. and mixwell. Transfer the emulsion to 100 mL vials using positive pressure,passing the material through a 0.22 micron filter in the process. Capand seal the vials.

EXAMPLE 44

A formulation of the present invention involves the following equipmentand steps: Microfluidizer, Model 110Y, Interaction chamber pressure14,000 PSI; Pressure vessels, 316 steel, 5 L and 12 L sizes; Filters,cellulose acetate, 0.22 micron; Filter holders, 142 mm. The followingsolutions were made: 33.3% (w/v) sucrose, 20 L; 150.0 g Pluronic P-123,150.0 g Zonyl FSO, 2.5 L, sonicate to aid dissolution (stock surfactantsolution). The Microfluidizer was primed with the sucrose solution. Theinteraction chamber, tubing, and cooling coil are covered with chippedice during the comminution process. To a 5 L pressure vessel with stirbar in an ice bath add sequentially: 1800 mL stock surfactant solution;333 g dodecafluoropentane. Pressurize vessel to 10 PSI with nitrogen for60 min while stirring. Pass the suspension through the Microfluidizer at14,000 PSI for 160 min and with a circulating water bath cooling theinteraction chamber to -3.0° C. Transfer the emulsion to a vesselcontaining 18 L of 33.3%, w/v, sucrose at 4° C. and mix for 45 min.Transfer the emulsion to 20 mL prechilled vials using positive pressure,passing the material through a 0.22 micron filter in the process. Capand seal the vials.

EXAMPLE 45

The dispersed phase of the present invention should be composed of ahigh vapor pressure chemical, such that, at the body temperature of theorganism to which the formulation is to be administered and which willbe examined following administration by ultrasound, a sufficientquantity of the chemical becomes a gaseous dispersion to provide adiagnostically useful alteration in the ultrasound data obtained duringthe examination. In a preferred embodiment, the dispersed phase can becomposed of any chemical which has a boiling point under standardpressure conditions below the body temperature of the organism which isto be administered the formulation and which will be examined followingadministration by ultrasound. Example 2 contains a table of the bodytemperatures of a number of species which can be used to select theappropriate dispersed phase for the formulations disclosed herein.

Under certain conditions, for example, organisms with febrile conditionsor studies done in medical facilities at high altitudes, where the airpressure is lower, chemicals which have boiling points up to 18° C.above the normal body temperature of the organism could have utility asthe dispersed phase for such ultrasound contrast agents.

Having set the upper temperature limit for selecting the dispersed phaselow boiling liquid, the lower limit is determined by the manufacturingmethod. If the available equipment contains only sealed vessels, and onecannot pressurize the reaction vessel during the formulation of thecolloidal dispersion, only dispersed phases with boiling points at orabove the freezing temperature of the continuous phase can be used. Forexample, a continuous phase containing ca 25% w/v iohexol has a freezingpoint near -6° C. Using such a continuous phase, any low boiling liquidwhich boils above -6° C. can thus be liquified by cooling alone.

However if one can pressurize the reaction vessel, for example with anitrogen tank operating at 30 lb. per sq in. pressure, one canpotentially liquify and thus disperse any low boiling liquid, even thoseboiling at temperatures below the freezing point of the continuousphase.

Example 44 describes a method of forming an emulsion with a dispersedphase liquid which boils above the freezing point of the continuousphase, while Example 48 below describes a method of forming an emulsionby the application of both pressure and refrigeration with a dispersedphase liquid which boils below the freezing point of the continuousphase liquid. Obviously, any chemical will be more efficiently dispersedby using some positive pressure, to lower the vaporization of thesematerials with the substantial vapor pressures that a low boiling pointimplies.

Having determined the appropriate boiling point of the dispersed phaseliquid, the actual chemicals which are useful can be quickly determinedby reference to standard texts, such as the CRC or a similar compendium.A listing of some, but not all, low boiling liquids arranged by boilingpoint follows:

    __________________________________________________________________________    Chemical List: Boiling Points in degrees Celcius                          Molecular                               Boiling                                   Chemical    Chemical Name         Weight                               Point                                   Group    __________________________________________________________________________    Neon                  20.18                               -246.0                                   11    Nitrogen (N2)         28.01                               -196.0                                   11    Argon                 39.98                               -189.4                                   10    Oxygen (O2)           32   -183.0                                   11    Methane               16.04                               -164.0                                   1    Krypton               83.8 -153.0                                   11    Nitric oxide          30.01                               -151.6                                   11    Methane, tetrafluoro  88   -129.0                                   3    Xenon                 131.29                               -108.0                                   11    Ethylene              28.05                               -103.7                                   1    Ethane                30.07                               -88.6                                   1    Nitrous oxide         44.01                               -88.5                                   11    Acetylene             26.04                               -84.0                                   1    Methane, nitroso-trifluoro                          99.01                               -84.0                                   3    Methane, trifluoro    70.02                               -84.0                                   3    Carbonyl fluoride     66.01                               -83.0                                   9    Ethylene, 1,2-difluoro                          64   -83.0                                   3    Ethylene, 1,1-difluoro                          64.04                               -83.0                                   3    Methane, trifluoro    70.01                               -82.2                                   3    Methane, chloro trifluoro                          104.46                               -81.4                                   3    Ethane, hexafluoro    138.01                               -79.0                                   3    Ethane, perfluoro     138.01                               -79.0                                   3    Methane, fluoro       34.03                               -79.0                                   3    Carbon dioxide        44.01                               -78.6                                   11    Methane, fluoro       34.03                               -78.4                                   3    Butyl nitrite         103.12                               -77.8                                   11    Ethylene, tetrafluoro 100.02                               -76.3                                   3    Sulfur hexafluoride   146.05                               -64.0                                   11    Trifluoroacetonitrile 95.02                               -64.0                                   10    Methane, bromo-trifluoro                          148.91                               -57.9                                   3    Methane, difluoro     52.02                               -51.6                                   3    Ethylene, trifluoro   82.03                               -51.0                                   3    Carbonyl sulfide      60.08                               -50.0                                   11    Propyne, 3,3,3-trifluoro                          94.04                               -48.3                                   3    Ethane, Pentafluoro   120  -48.0                                   3    Propene               42.08                               -47.4                                   1    Ethane, 1,1,1-trifluoro                          84.04                               -47.3                                   3    Propane               44.1 -42.1                                   1    Ethane, nitroso-pentafluoro                          149.02                               -42.0                                   3    Methane, chloro-difluoro                          86.47                               -40.8                                   3    Propyl, 1,1,1,2,3,3-hexafluoro-2,3-difluoro                          221  -39.03                                   3    Allene, tetrafluoro   112.03                               -38.0                                   3    Ethane, 1-chloro-1,1,2,2,2-pentafluoro                          154.47                               -38.0                                   3    Ethane, chloro pentafluoro                          154.47                               -38.0                                   3    Ethane, fluoro        48.06                               -37.7                                   3    Dimethylamine, perfluoro                          171.02                               -37.0                                   10    Propane, perfluoro    188.02                               -36.0                                   3    Ethyl amine, perfluoro                          171.02                               -35.0                                   10    Allene                40.06                               -34.5                                   1    Cyclopropane          42.08                               -32.7                                   1    Trifluoromethyl peroxide                          170.01                               -32.0                                   11    Azomethane, hexafluoro                          166.03                               -31.6                                   11    Methane, nitro-trifluoro                          115.01                               -31.1                                   3    Acetylene-chloro      60.48                               -30.0                                   3    Methane, dichloro difluoro                          120.91                               -29.8                                   3    Propylene, perfluoro  150.02                               -29.4                                   3    Acetone, hexafluoro   166.02                               -28.0                                   3    Ethane, 1,1,2,2-tetrafluoro                          102.03                               -27.0                                   3    Ethane, 1,1,1,2-tetrafluoro                          102.03                               -26.5                                   3    Ethylene, 1-chloro-1,2,2-trifluoro                          116.47                               -26.2                                   3    Ethylene, chloro trifluoro                          116.47                               -26.2                                   3    Methyl ether          46.07                               -25.0                                   6    Ethane, 1,1-difluoro  66.05                               -24.7                                   3    2-Butyne, perfluoro   162.03                               -24.6                                   3    Ethylene, 1-chloro-1-fluoro                          80.5 -24.0                                   3    Propyne               40.06                               -23.2                                   1    Methane, iodo-trifluoro                          195.91                               -22.5                                   3    Trifluoromethyl sulfide                          170.07                               -22.2                                   11    Methane sulfonyl fluoride, trifluoro                          152.06                               -21.7                                   3    Propene, 3,3,3-trifluoro                          96.05                               -21.0                                   3    Propene, 1,1,1,3,3-Pentafluoro                          132.04                               -21.0                                   3    Methane, (pentafluorothio)trifluoro                          196.06                               -20.0                                   3    Ethane, 1,1,2,2-Tetrafluoro                          102.04                               -19.7                                   3    Ethylene, 2-chloro-1, 1-difluoro                          98.5 -17.7                                   3    Propane, 2-H-heptafluoro                          170.03                               -15.0                                   3    Propane, 1,1,1-trifluoro                          98.07                               -13.0                                   3    Methane, bromo difluoro nitroso                          159.92                               -12.0                                   3    Methyl nitrite        61.04                               -12.0                                   11    Propane, heptafluoro-1-nitroso                          199.03                               -12.0                                   3    Ethane, 2-chloro-1,1,1,2-tetrafluoro                          136.48                               -12.0                                   3    Isobutane             58.12                               -11.6                                   1    Ethane, 1-chloro-1,1,2,2-tetrafluoro                          136.48                               -10.0                                   3    Propane, 2-fluoro     62.09                               -10.0                                   3    Methane, chloro fluoro                          68.48                               -9.1                                   3    lsobutylene           56.11                               -6.9                                   1    Dimethyl amine, hexafluoro                          153.03                               -6.7                                   10    1-Butene              56.11                               -6.3                                   1    Nitrosyl chloride     65.47                               -5.5                                   11    1,3-Butadiene         54.09                               -4.4                                   1    Cyclobutane, octafluoro                          200.03                               -4.0                                   3    Propylene, 3-fluoro   60.07                               -3.0                                   3    Dimethyloxonium chloride                          82.53                               -2.0                                   3    Propane, 2-chloroheptafluoro                          204.47                               -2.0                                   3    Propane, 1,1,1,2,2,3-Hexafluoro                          152.04                               -1.4                                   3    Propane, 1,1,1,3,3,3-Hexafluoro                          152.05                               -1.1                                   3    Methanesulfenylchloride, trifluoro                          136.52                               -0.7                                   3    n-Butane              58.12                               -0.5                                   1    Propane, 2,2-difluoro 80.08                               -0.4                                   3    Ethane, 2-chloro, 1,1-difluoro                          100  -0.1                                   3    Ethane, nitro-pentafluoro                          165.02                               0.0 3    2-Butene, perfluoro   200.03                               0.0 3    Acetylene, isopropyl  68   0.0 1    2-Butene {trans}      56.11                               0.9 1    1,2-Benzanthracene, 4-methyl                          242.32                               1.0 2    Propane, 1,1,1,2,2,3-hexafluoro                          152.04                               1.2 3    2-Butene, octafluoro  200.04                               1.2 3    Azomethane            58.08                               1.5 11    Phthalic acid, tetrachloro                          303.91                               2.0 3    Trimethyl amine       59.11                               2.9 10    Cyclobutene, perfluoro                          162.03                               3.0 3    1-Butene, 3,3,4,4,4-Pentafluoro                          146  3.0 3    Ethane, 1,2-dichloro-1,1,2,2-tetrafluoro                          170.92                               3.0 3    Ethane, 1,1-dichloro-1,2,2,2-tetrafluoro                          170.92                               3.6 3    2-Butene {cis}        56.11                               3.7 1    Ethane, 1,2-dichlorotetrafluoro                          170.92                               3.8 3    Butane, decafluoro    238.03                               4.0 3    Cyclopropane, methyl  56.11                               4.0 1    Ethane, dichlorotrifluoro                          152  4.0 3    Acetylene-bromo       104.93                               4.7 3    1-Butene, perfluoro   200.03                               4.8 3    Benzoyl chloride, pentachloro                          312.79                               5.0 3    Ethane, 1,1,2-trifluoro                          84.04                               5.0 3    Vinyl acetylene       52.08                               5.1 1    1,3-Butadiene, hexafluoro                          162.03                               6.0 3    Propene, 2-trifluoromethyl                          110.08                               6.0 3    Methanethiol          48.1 6.2 11    Propane, 1,1,1,2,3,3-Hexafluoro                          152.04                               6.5 3    Carbon suboxide       68.03                               6.8 11    Ethane, 2-chloro-1,1,1-trifluoro                          118.49                               6.9 3    Fulvene               78.11                               7.0 11    Dimethyl amine        45.08                               7.4 10    Propane, 2-chloro-1, 3-difluoro                          114.51                               8.0 3    1-Butyne              54.09                               8.1 1    Methane, dichloro-fluoro                          102.92                               9.0 3    Neopentane            72.15                               9.5 1    Ethylene, 1-chloro-2-fluoro                          80.5 10.0                                   3    Butadiyne             50.06                               10.3                                   1    1,2-Butadiene         54.09                               10.8                                   1    Ethyl methyl ether    60.1 10.8                                   6    1,3-Butadiene, 2-fluoro                          72.08                               12.0                                   3    Crotononitrile        67.09                               12.0                                   11    Cyclobutane           56.11                               12.0                                   1    Isobutane, 1,2-epoxy-3-chloro                          106.55                               12.0                                   3    Methyl vinyl ether    58.08                               12.0                                   6    Propane, 1-bromo-heptafluoro                          248.9                               12.0                                   3    Ethane, idopentafluoro                          245.9                               12.0                                   3    Propane, 2-(trifluoromethyl)-1,1,1,3,3,3-hexafluoro                               211 12.03    Ethane, Chloro        64.51                               12.3                                   3    Diazoethane, 1,1,1-trifluoro                          110.04                               13.0                                   3    2-Butene, 3-methyl    68   14.0                                   1    Methane, disilano     76.25                               14.7                                   11    Ethyl nitrite         75.07                               16.0                                   11    Ethyl amine           45.08                               16.6                                   10    Tungsten hexafluoride 298  17.5                                   11    2,3-Dimethyl-2-norbornano                          140.23                               19.0                                   11    Ethylene, 1,1-dichloro-2, 2-difluoro                          133  19.0                                   3    Methane, bromo fluoro 112.93                               19.0                                   3    1-Butene, 3-methyl    70.13                               20.0                                   1    Borine, trimethyl     55.91                               20.0                                   11    Fluorinert, FC-87 (3M Trade Mark)                          Unknown                               20.0                                   3    Cyclopropane, 1,1-dimethyl                          70.13                               20.6                                   1    Acetaldehyde          44.05                               20.8                                   7    Acetyl flouride       62.04                               20.8                                   9    Borine, dimethyl, methoxy                          71.19                               21.0                                   11    Ethylene, 1,2-dichloro-1,2-difluoro                          132.92                               21.1                                   3    Ethylene, dichloro difluoro                          132.92                               21.1                                   3    Methane, difluoro-iodo                          177.92                               21.6                                   3    Diacetylene           50.08                               22.0                                   1    Propylene, 2-chloro   76.53                               22.6                                   3    Carvone- {d}          150.22                               23.0                                   11    Methane, trichlorofluoro                          137.37                               23.7                                   3    1,3-Dioxolane-2-one, 4-methyl                          102.09                               24.2                                   1    Methane, dibromo difluoro                          209.82                               24.5                                   3    2-Pentanone, 4-amino-4-methyl                          115.18                               25.0                                   10    Methane, chloro difluoro nitro                          131.47                               25.0                                   3    Propane, heptafluoro-1-nitro                          215.03                               25.0                                   3    Cyclopentene, 3-chloro                          102.56                               25.0                                   3    1,4-Pentadiene        68.12                               26.0                                   1    1,5-Heptadiyne        92.14                               26.0                                   1    3-Butene-2-one, 4-phenyl {trans}                          146.19                               26.0                                   2    Propane, 1,1,2,2,3-Pentafluoro                          134.06                               26.0                                   3    2-Butyne              54.09                               27.0                                   1    Ethane, 2,2-dichloro-1,1,1-trifluoro                          152.9                               27.0                                   3    Cyclopentene, Octafluoro                          211.05                               27.0                                   3    1-Nonene-3-yne        122.21                               27.0                                   1    2-Methyl butane       72.15                               27.8                                   1    Butane, 2-methyl      72.15                               27.8                                   1    Ethane, 1,2-dichlorotrifluoro                          152.9                               28.0                                   3    Ether, difluoromethyl 2,2,2-trifluoroethyl                          150.05                               28.0                                   3    Cyclopropane, 1,2-dimethyl {trans, l}                          70.13                               28.0                                   1    Vinyl ether           70   28.0                                   6    Cyclopropane, 1,2-dimethyl {trans, dl}                          70.13                               29.0                                   1    Toluene, 2,4-diamino  122.17                               29.0                                   2    1-Pentene, perfluoro  250.04                               29.0                                   3    1-Butyne, 3-methyl    68.12                               29.5                                   1    1-Pentene             70.13                               30.0                                   1    1-Pentene, 3,3,4,4,5,5,5-heptafluoro                          196  30.0                                   3    Ethylene, idotrifluoro                          207.9                               30.0                                   3    Styrene, 3-fluoro     122.14                               30.0                                   11    1-Pentene, 3-bromo    149.03                               30.5                                   3    Pentane, perfluoro    288.04                               30.5                                   3    Ethane, 1,2-difluoro  66.05                               30.7                                   3    Butane, 3-methyl, 1,1,1-trifluoro                          126.12                               31.0                                   3    1-Butene, 2-methyl    70.13                               31.2                                   1    Formic acid, methyl ester                          60.05                               31.5                                   9    Methane sulfonyl chloride, trifluoro                          168.52                               31.6                                   3    Ethane, 1,1-dichloro-1-fluoro                          116.95                               32.0                                   3    Pentane, 1-fluoro     90.14                               32.0                                   3    Acetylene-diido       277.83                               32.0                                   3    Propane, 2-amino      59.11                               32.4                                   10    Butane, 1-fluoro      76.11                               32.5                                   3    Methyl isopropyl ether                          74.12                               32.5                                   6    Propylene, 1-chloro   76.53                               32.8                                   3    Butyraldehyde, 2-bromo                          151  33.0                                   3    2-Butene, 2-chloro-1,1,1,4,4,4-hexafluoro                          198.5                               33.0                                   3    1,3-Butadiene, 1,2,3-trichloro                          157.43                               33.0                                   3    Butene, 2-chloro-1,1,1,4,4,4-hexafluoro                          199  33.0                                   3    bis-(Dimethyl phosphino) amine                          137.1                               33.5                                   10    1,3-Butadiene, 2-methyl                          68.12                               34.0                                   1    1-Butene-3-yne, 2-methyl                          66.1 34.0                                   1    Isoprene              68.12                               34.0                                   1    Methane, chloro dinitro                          140.48                               34.0                                   3    Propane, 1,2-epoxy    58.08                               34.3                                   6    Cyclopropane, ethyl   70.13                               34.5                                   1    Ethyl ether           74.12                               34.5                                   6    Dimethyl disulfide, hexafluoro                          202.13                               34.6                                   11    Ethylene, 1,2-dichloro-1-fluoro                          115  35.0                                   3    Propane, 1,2-dichlorohexafluoro                          220.93                               35.0                                   3    Ethyl vinyl ether     72.11                               35.0                                   6    Propane, 2-chloro     78.54                               35.7                                   3    Methane, bromo-chloro-fluoro                          147.37                               36.0                                   3    Piperidine, 2,3,6-trimethyl                          127.23                               36.0                                   11    1,2,3-Nonadecane tricarboxylic acid, 2-                          500.72                               36.0                                   9    ....hydroxy, trimethylester    Dimethyl ethyl amine  73.14                               36.0                                   10    n-Pentane             72.15                               36.1                                   1    2-Pentene {trans}     70.13                               36.3                                   1    Cyclobutane, methyl   70.13                               36.3                                   1    Ethyl methyl amine    59.11                               36.7                                   10    2-Pentene {Cis}       70.13                               36.9                                   1    Cyclopropane, 1,2-dimethyl {cis}                          70.13                               37.0                                   1    Ethylene, 1,1-dichloro                          96.94                               37.0                                   3    Propylene, 1-chloro-{trans}                          76.53                               37.4                                   3    Ethylene, 1,1-dichloro-2-fluoro                          114.93                               37.5                                   3    Methane, dichloro     84.93                               40.0                                   3    Methane, iodo-        141.94                               42.4                                   3    Ethane, 1,1-dichloro  98   57.3                                   3    __________________________________________________________________________

CHEMICAL GROUP DESIGNATION

1 Aliphatic hydrocarbons and/or derivatives

2 Aromatic hydrocarbons and/or derivatives

3 Organic halides and/or derivatives

6 Ethers and/or derivatives

7 Aldehydes and/or derivatives

9 Carboxylic acids and/or derivatives

10 Amines and/of derivatives

11 Miscellaneous

EXAMPLE 46

The dispersed phase can also be selected from a group of azeotropes bythe principles and criteria as set down in Example 45. A listing ofsome, but not all binary azeotropes, with the boiling points follows:

Acetone (21%)-Pentane (79%) 32° C.; Ethyl ether (48%)-Isoprene (52%) 33°C.; Ethyl ether (44%)-methyl for XXX (56%) 28° C.; Ethyl ether(98.8%)-Water (1.2%) 34° C.; Isoprene (86%)-2-methyl-2-butane (14%) 34°C.; Isopropyl chloride (99%)-Water (1%) 35° C.; Methyl vinyl chloride(99.1%)-Water (0.9%) 33° C.; Pentane (98.6%)-Water (1.4%) 34° C.; Vinylethyl ether (98.5%)-Water (1.5%) 34° C.

A listing of some but not all ternary azeotropes, with the boiling pointfollows:

Acetone (7.6%)-Isoprene (92%)-Water (0.4%) 32° C.; Carbon disulfide(4/XXX(46.2%)-Methanol (64.7%)-Methyl acetate (57%) 37° C.: Carbondisulfide (55%)-Methanol (7%)-Methylal (38%) 35° C.;

EXAMPLE 47

The colloidal dispersions of the present invention are distinct anddiffer from prior art emulsions for ultrasound contrast in that at leastsome portion of the dispersed phase percolates or vaporizes followingadministration to an organism. The presence of this dispersed materialwith a distinct liquid-gas interface provides the basis for the strongbackscatter of the acoustic beam.

One test of the presence of a dispersed gas phase emulsion is theresponse of the ultrasound backscatter from the dispersion to changes inpressure. While true liquid dispersions are largely insensitive tocompressive forces, a gaseous colloidal dispersion will show a decreasein acoustic backscatter when pressure is applied, due to compression ofthe gas and a decrease in the effective backscatter cross section.

With the experimental system of Example 1, the acoustic backscatter in asealed beaker was tested through an acoustic window. Then pressure wasapplied to the system and rerecording the acoustic backscatter recorded.Since the acoustic backscatter differed significantly following theapplication of pressure it was concluded that the dispersed phasecontains some portion in the gas state.

EXAMPLE 48

A formulation df the present invention can be made by condensation ofthe dispersed phase from the gas state rather than comminution from theliquid state and involves the following equipment and steps:Microfluidizer, Model 110Y, Interaction chamber pressure 14,000 PSI;Pressure vessels, 316 steel, 5 L and 12 L sizes; Filters, celluloseacetate, 0.22 micron; Filter holders, 142 mm. The following solutionswere made: 36% iohexol, 10 L; 41.75 g Pluronic P-123, 41.75 g Zonyl FSO,2.5 L, sonicate to aid dissolution (stock surfactant solution). TheMicrofluidizer was primed with the iohexol solution and the entirecontainer cooled to -6° C. The interaction chamber, tubing, and coolingcoil are covered with chipped ice during the condensation process. To a5 L pressure vessel with stir bar in an ice bath add 1800 mL stocksurfactant solution. A tank of propane (boiling point -42° C.) wasattached to the interaction chamber by gas tight fittings and thechamber charged with 200 g of propane. The entire vessel was pressurizedto 10 PSI with nitrogen for 45 min while stirring. The suspension waspassed through the Microfluidizer for 30 min at 5,000 PSI for 60 min at14,000 PSI. The emulsion was transferred to a vessel containing 8 L ofwater at 40° C. and mixed well and transferred to 100 mL vials usingpositive pressure, passing the material through a 0.22 micron filter inthe process. Cap and seal the vials.

Other emulsions containing other low boiling materials of Example 45 canbe made in a similar manner by varying the dispersed phase and beingcertain the pressure and temperature are sufficient to liquify thedispersed phase material.

EXAMPLE 49

The dispersed phase can be composed of any chemical which has a boilingpoint under standard pressure conditions below the body temperature ofthe organism to which the formulation is to be administered and whichwill be examined following administration by ultrasound. Example 45discusses how one selects suitable chemicals for the dispersed phasebased on the temperature range obtained by consideration of the boilingpoint of the selected chemical and parameters of the manufacturingprocess.

Having determined that the boiling point under standard conditions ofpressure is preferably below approximately 37° C., it has been foundthat selecting chemicals by the total number of atoms present providesan alternative method of selecting suitable materials as ultrasoundcontrast agents. A listing of suitable chemicals, arranged by totalatoms present, reveals that all preferred chemicals contain between fourand seventeen atoms and follows:

    __________________________________________________________________________    Chemical List Boiling Points in degrees Celcius                         Total                             Molecular                                   Molecular                                        Boiling    Name                 Atoms                             Formula                                   Weight                                        Point    __________________________________________________________________________    bromo-methane        4   CH3Br 94.94                                        3.2    bromo-difluoro-methane                         5   CHBrF2                                   130.92                                        -14.15    chloro-fluoro-methane                         5   CH2ClF                                   68.48                                        -9.15    bromo-trideuterio-methane                         5   CD3Br 12   2.8    propadienedione      5   C3O2  68.03                                        6.8    dicholoro-fluoro-methane                         5   CHCl2F                                   102.92                                        8.9    methaneselenol       5   CH4Se 95   12    difluoro-iodo-methane                         5   CHF21 177.92                                        21.6    dibromo-difluoro-methane                         5   CBr2F2                                   209.82                                        22.79    trichloro-fluoro-methane                         5   CCl3F 137.7                                        23.65    bromo-chloro-fluoro-methane                         5   CHBrClF                                   147.37                                        36.11    2-chloro- 1,1-difluoro-ethene                         6   C2HClF2                                   98.48                                        -18.6    trifluoro-methaneselenol                         6   CHF3Se                                   148.97                                        -14.5    chloro-ethene        6   C2H3Cl                                   62.5 -13.9    oxalyl fluoride      6   C2F2O2                                   94.02                                        -2.7    formamide            6   CH3NO 45.04                                        2.18    2-bromo- 1,1-difluoro-ethene                         6   C2HBrF2                                   142.93                                        5.7    methanethiol         6   CH4S  48.1 5.9    butadiyne            6   C4H2  50.06                                        9    bromo-ethene         6   C2H3Br                                   106.95                                        15.6    1,1- dichloro-2,2-difluoro-ethene                         6   C2Cl2F2                                   132.92                                        18.9    trans-1- bromo-2-fluoroethylene                         6   C2H2BrF                                   124.94                                        19.8    bromo-methane        4   CH3Br 94.94                                        3.2    1,1- dichloro-2,2-difluoroethene                         6   C2Cl2F2                                   132.92                                        20    1,1-dichloro-ethene  6   C2H2Cl2                                   96.94                                        31.8    trans-1,2 Dichlorfluoroethylene                         6   C2HCl2F                                   114.93                                        37    cis Dichlorofluoroethylene                         6   C2HCl2F                                   114.93                                        37    1,1 dichloro-2-fluoro-ethene                         6   C2HCl2F                                   114.93                                        37    Methyldifluoramine   7   CH3F2N                                   67.02                                        -16    difluorophosphoric acid methyl ester                         7   CH3F2OP                                   100  -15.5    methylamine          7   CH5N  31.06                                        -6.5    dichloro-methyl-borane                         7   CH3BCl2                                   96.75                                        11.5    tetrachloro-1,2-difluoro-ethane                         8   C2Cl4F2                                   203.83                                        37.5    1,1,2- trichloro-ethane                         8   C2H3Cl3                                   133.4                                        -24    1,1,1,2-tetrachloro-ethane                         8   C2H2Cl4                                   167.85                                        -16.3    1-chloro- 1,1-difluoro-ethane                         8   C2H3ClF2                                   100.5                                        -9.8    1,2-dibromo-1,1-dichloro-ethane                         8   C2H2Br2Cl2                                   256.75                                        1.78    1,1-dichloro-tetrafluoro-ethane                         8   C2Cl2F4                                   170.92                                        3    1,1,2-trifluoro-ethane                         8   C2H3F3                                   84.04                                        3    1,2-dichloro-tetrafluoro-ethane                         8   C2Cl2F4                                   170.92                                        3.5    Tetrafluor-(methyl-methylamine)                         8   C2HF4N                                   115.03                                        5    butenyne             8   C4H4  52.08                                        5.11    2-chloro-1,1,1-trifluoro-ethane                         8   C2H2ClF3                                   118.49                                        6    Fluorcarbonyl-trifluormethyl-sulfane                         8   C2F4OS                                   148.08                                        8    chloro-methyl-silane 8   CH5ClSi                                   80.59                                        8    1,2-difluoro-ethane  8   C2H4F2                                   66.05                                        10    chloro-ethane        8   C2D5Cl                                   64.51                                        12    pentafluoro-iodo-ethane                         8   C2F5I 245.92                                        12.5    2- diazo-1,1,1-trifluoro-ethane                         8   C2HF3N2                                   110.04                                        13    1-chloro- 1-fluoro-ethane                         8   C2H4ClF                                   82.31                                        16    1,1,2- tetrachloro-ethane                         8   C2H2Cl4                                   167.85                                        16.3    1,12- trichloro-ethane                         8   C2H3Cl3                                   133.4                                        24    2- bromo-1,1,1-trifluoro-ethan                         8   C2H2BrF3                                   162.94                                        26    Chlormethyl-trifluor-silane                         8   CH2ClF3Si                                   134.56                                        26    1,2- difluoro-ethane 8   C2H4F2                                   66.05                                        30.7    2-chloro-1,1-difluoro-ethane                         8   C2H3ClF2                                   100.05                                        35.1    tetrachloro-1,2-difluoro-ethane                         8   C2Cl4F2                                   203.83                                        37.5    bromo-pentadeuterio-ethane                         8   C2BrD5                                   114  38    dimethyl-silane      9   C2H8Si                                   60.1 -20    Pentafluor-cyclopropane                         9   C3HF5 132.03                                        -9    difluoromethyl-trifluoromethyl sulfide                         9   C2HF5S                                   152.08                                        0.8    1,1,2,3,3- pentafluoro-propene                         9   C3HF5 132.03                                        1.8    Chlorpentafluorcyclopropane                         9   C3ClF5                                   166.48                                        3    Germlacetylene       9   C2H4Ge                                   100.64                                        3.85    rans-1,1,2,3 Tetrafluorcyclopropane                         9   C3H2F4                                   114.04                                        6    2- chloro-pentafluoro-propene                         9   C3ClF5                                   166.48                                        6.7    3- chloro-pentafluoro-propene                         9   C3ClF5                                   166.48                                        7.3    1- chloro-pentafluoro-propene                         9   C3ClF5                                   166.48                                        8    fluoro-methyl-methyl ether                         9   C2H5F0                                   64.06                                        19    Brompentafluorcyclopropane                         9   C3BrF5                                   210.93                                        20.5    Vinyloxy-acetylene   9   C4H4O 68.08                                        22    2- chloro-propene    9   C3H5Cl                                   76.53                                        22.6    cis-trans-l-Chlor-1,2,2,3-tetrafluorcylclopropane                         9   C3HClF4                                   148.49                                        24.5    3-bromo-pentafluoro-propene                         9   C3BrF5                                   210.93                                        26.5    2,2-dichloro-1,1,1-trifluoro-ethane                         9   C3HCl3F3                                   152.93                                        27    Furan                9   C4H40 68.08                                        31    1-chloro-propene     9   C3H5Cl                                   76.53                                        32.1    2-Chlor-vinyl-trifluorsilane                         9   C2H2ClF3Si                                   146.57                                        33    cis-1,1,2,3 Tetrafluorcyclopropane                         9   C3H2F4                                   114.04                                        34    3-bromo-1,1,3,-tetrafluoro-propene                         9   C3HBrF4                                   192.94                                        34    ethanethiol          9   C2H6Si                                   62.13                                        35    dimethyl sulfide     9   C2H6S 62.13                                        36    (chloro-fluoro-methyl)-trifluoromethyl                         9   C2HClF4S                                   168.54                                        37    sulfide    1 t- chloro-propane  9   C3H5Cl                                   76.53                                        37.2    buta-1,3-diene       10  C4H6  54.09                                        -4.6    1,5-Dicarbaclosotriborane                         10  C2H5B3                                   61.49                                        -3.7    omega-Nitrosoperfluorpropionnitrile                         10  C3F4N20                                   156.04                                        2    pentafluoro-propionaldehyde                         10  C3HFS0                                   148.03                                        2    1,1- difluoro-buta-1,3-diene                         10  C4H4F2                                   90.07                                        3.5    methyl-vinyl ether   10  C3H60 58.08                                        5    hexafluoro-buta-1,3-diene                         10  C4F6  162.03                                        5.8    but-1-yne            10  C4H6  54.09                                        7.9    1-Deutero-1-butane   10  C4H5D 55.1 8    methylene-cyclopropane                         10  C4H6  54.09                                        8.8    buta-1,2-diene       10  C4H6  54.09                                        10.84    2-fluoro-buta-1,3-diene                         10  C4H5F 72.08                                        11.5    1H-pentafluoro-but-1-yne                         10  C4HF5 144.04                                        12    pentafluoro-acetone  10  C3HF50                                   148.03                                        13.5    Difluoraminoethane   10  C2H5F2N                                   81.07                                        14.9    Tetra-B-fluor-B,B'-ethenediyl-                         10  C2H2B2F4                                   123.65                                        15    bis-borane    cis-1- Fluor-1,3-butadiene                         10  C4H5F 72.08                                        15.6    trans-1- Flour-1,3-butadiene                         10  C4H5F 72.08                                        16    ethylamine           10  C2H7N 45.08                                        16.6    dimethyl-phosphine   10  C2H7P 62.05                                        20    N- Methyl-imino-schwefel-tetra-fluoride                         10  CH3F4NS                                   137.1                                        21.8    Methylschwefelpentafluoride                         10  CH3F5S                                   142.09                                        26    but-2-yne            10  C4H6  54.09                                        26.97    bromo-pentafluoro-acetone                         10  C3BrF50                                   226.93                                        31    bromo-dimethyl-borane                         10  C2H6BBr                                   120.78                                        31.75    1- chloro-2,3,3,4,4-pentanfluoro-                         10  C4ClF5                                   178.49                                        33    cyclobutene    bis- trifluoromethyl disulfide                         10  C2F6S2                                   202.13                                        34    (±)(1)1,2- epoxy-propane                         10  C3H60 58.08                                        34.23    ethyl-silane         11  C2H8Si                                   60.17                                        -14    1,1,1- trifluoro propane                         11  C3H5F3                                   98.07                                        -13    2- fluoro-propane    11  C3H7F 62.09                                        -11    Perfluormethoxyacetylfluoride                         11  C3F602                                   182.02                                        -9.7    ethyl-trifluoro-silane                         11  C2H5F3Si                                   114.14                                        -4.4    1-fluoro-propane     11  C3H7F 62.09                                        -3    2,2-difluoro-propane 11  C3H6F2                                   80.08                                        -0.6    1,1,1,3,3,3-hexafluoro-propane                         11  C3H2F6                                   152.04                                        1.2    Perfluorcyclobutanone                         11  C4F60 178.03                                        1    1,1,1,2,2,3-hexafluoro-propane                         11  C3H2F6                                   152.04                                        1.2    2- chloro-heptafluoro-propane                         11  C3ClF7                                   204.47                                        2.2    dideuterio-dimethyl germane                         11  C2H6D2Ge                                   106.69                                        6.5    1,1- difluoro-propane                         11  C3G6F2                                   80.08                                        7    ethyl-trideuterio germane                         11  C2H5D3Ge                                   107.69                                        11.3    disilanyl-methane    11  CH8Si2                                   76.25                                        14    1-chloro- 1,1,2,2-tetrafluoro-propane                         11  C3H3ClF4                                   150.5                                        19.93    Trifluorosilydimethylamine                         11  C2H6F3NSi                                   129.16                                        21    ethylidene-methyl-amine                         11  C3H7N 57.1 27.5    disilanyl-methane    11  CH8Si2                                   76.25                                        28    divinyl ether        11  C4H60 70.09                                        28    1,1,1,3- tetrafluoro-propane                         11  C3H4F4                                   116.06                                        29.4    1- Sila-3-germapropane                         11  CH8GeSI                                   120.75                                        30    2- chloro-1,1,1-trifluoro-propane                         11  C3H4ClF3                                   132.51                                        30    2- methyl-but-1-en-3-yne                         11  C5H6  66.1 32    Bis-trifluorsilyldichlormethane                         11  CCl2F6Si2                                   253.08                                        34    1,2- dichloro-hexafluoro-propane                         11  C3Cl2F6                                   220.93                                        34.8    2- chloro-propane    11  C3H7Cl                                   78.54                                        34.8    ethyl-vinyl ether    11  C2H80 72.11                                        35    3-methylen-oxetane   11  C4H60 70.09                                        35    2-chloro-2-fluoro-propane                         11  C3H6ClF                                   96.53                                        35.2    Bis-trifluorsilylmethan                         11  CH2F6Si2                                   184.19                                        35.5    chloro-dimethyl-silane                         11  C2H7ClSi                                   94.62                                        35.7    1,3 dichloro-hexafluoro-propane                         11  C3Cl2F6                                   220.93                                        36.1    Bis-trifluorsilylchlormethane                         11  CHClF6Si2                                   218.63                                        37    heptafluoro-1-nitroso-propane                         12  C3F7N0                                   199.03                                        -9.5    1,1,2,2,3-pentafluoro-3-trifluoromethyl-                         12  C4F8  200.03                                        -9    cyclopropane    2-methyl-propenc     12  C4H8  56.11                                        -6.9    octafluoro-cyclobutane                         12  C4F8  200.03                                        -6.42    but-1-ene            12  C4H8  56.11                                        -6.3    1,1,2,2-Tetrafluor-2-trifluormethoxy-                         12  C3HF70                                   186.03                                        -2    aethane    cis-octafluoro-butene-(2)                         12  C4F8  200.03                                        0.4    methyl-cyclopropane  12  C4H8  56.11                                        0.7    but-2 t-ene          12  C4H8  56.11                                        0.88    butene-(2)           12  C4H8  56.11                                        1    heptafluoro-butyronitrile                         12  C4F7N 195.04                                        1    octafluoro-but-2-ene 12  C4F8  200.03                                        1.2    1,1-difluoro-but-1-ene                         12  C4H6F2                                   92.09                                        3.71    but-2 c-ene          12  C4H8  56.11                                        3.72    octafluoro-but-1-ene 12  C4F8  200.03                                        4.8    1,1,1,4,4,4-Hexafluor-2-butene                         12  C4H2F6                                   164.05                                        5.4    trifluormethylethylether                         12  C3H5F30                                   114.07                                        5.5    2H,3H- hexafluoro-but-2 t-ene                         12  C4H2F6                                   164.05                                        6    3,3,3- trifluoro-2-methyl-propene                         12  C4H5F3                                   110.08                                        6    ethyl-methyl ether   12  C3H80 60.1 6.6    2H- Heptafluor-buten-(1)                         12  C4HF7 182.04                                        10    cyclobutane          12  C4H8  56.11                                        12    pentafluoro-2-methyl-propene                         12  C4H3F5                                   146.06                                        12.8    Methyl-vinylsilane   12  C3H8Si                                   72.18                                        13.7    1,1,1- trifluoro-but-2 t-ene                         12  C4H5F3                                   110.08                                        20    1,1,1- trifluoro-but-2 t-ene                         12  C4H5F3                                   110.08                                        20    Allyltrifluorsilane  12  C3H5F3Si                                   126.15                                        21    1,1,2 Trifluor-2-trifluormethylcyclopropane                         12  C4H2F6                                   164.05                                        21.5    1,1,2- Trifluor-1-chlor-2-trifluormethoxy-                         12  C3HClF60                                   202.48                                        23    aethane    heptafluoro-propane-1-thiol                         12  C3HF7S                                   202.9                                        23.7    (2- Brom-1,1,2,2-tetrafluor-ethyl)-                         12  C3BrF70                                   264.93                                        24    trifluormethyl-ether    Cyclopropylsilane    12  C3H8Si                                   72.18                                        26.8    3,3 difluoro-2-methyl-propene                         12  C4H6F2                                   92.09                                        28.1    1,1,2,2- Tetrafluorethyldifluormethylether                         12  C3H2F60                                   168.04                                        28.5    2,2,2 Trifluorethyl-difluormethylether                         12  C3H3F50                                   150.05                                        29    1,1,1- trifluoro-2-methoxy-ethane                         12  C3H5F30                                   114.07                                        31    2- chloro-heptafluoro-but-2-ene                         12  C4C1F7                                   216.49                                        32.2    Pentafluoronitroacetone                         12  C3F5N03                                   193.03                                        32.6    2H,3H hexafluoro-but-2 c-ene                         12  C4H2F6                                   164.05                                        33.2    2- chloro-3H-hexafluoro-but-2-ene                         12  C4HClF6                                   198.5                                        34.4    tetra-B-fluoro-B,B'-ethanediyl-                         12  C2H4B2F4                                   125.67                                        35    bis-borane    Ethyl-trifluormethyl-sulfide                         12  C3H5F3S                                   130.13                                        35    methyl-(1,1,2,2-tetrafluoro-                         12  C3H4F40                                   132.06                                        36.5    ethyl)-ether    ( Chlor-difluormethyl)-(2,2,2-trifluor-                         12  C3H2ClF50                                   184.49                                        37    ethyl)-ether    1,1,2- Trifluor-1,2-dichlor-2-                         12  C3Cl2F60                                   236.93                                        37    trifluormethoxy-aethane    1- Nitroso-2-trifluormethoxy-                         13  C3F7NO2                                   215.03                                        -10    tetrafluorethane    Nonafluor-2-azabutane                         13  C3F9N 221.03                                        -3.8    trimethyl-amine      13  C3H9N 59.11                                        3.5    3,3- Dimethyl-cyclopropene                         13  C5H8  68.12                                        18    penta-1,4-diene      13  C5H8  68.12                                        24    3- methyl-but-1-yne  13  C5H8  68.12                                        26    3- Methyl-cyclobutene                         13  C5H8  68.12                                        27.5    Trifluormethanazo-2,2,2-                         13  C3H2F6N2                                   180.05                                        28    trifluoraethane    2- methyl-buta-1,3-diene                         13  C5H8  68.12                                        30    alpha-Nitroso-perfluorisobutyronitrile                         13  C4F6N20                                   206.05                                        31    isopropylamine       13  C3H9N 59.11                                        31.7    2- Methoxyperfluoropropene                         13  C4H3F50                                   162.06                                        32    Dimethylethinylsilane                         13  C4H8Si                                   84.19                                        32    1,1,2,2- Tetradeuterospiropentane                         13  C5H4D4                                   72.14                                        33    dimethoxy-silane     13  C2H802Si                                   92.17                                        33.5    isopropenyl-methyl ether                         13  C4H80 72.11                                        34    tert-butyl-silane    13  C4Hl2Si                                   88.22                                        34.4    spiropentane         13  C5H8  68.12                                        35    3,4,4- Trifluorisoprene                         13  C5H5F3                                   122.09                                        35    1- methyl-cyclobutene                         13  C5H8  68.12                                        37    2- methyl-propane    14  C4H10 58.12                                        -13.3    decafluoro-butane    14  C4F10 238.03                                        -1.7    1- deuterio-butane   14  C4H9D 59.13                                        -0.5    butane               14  C4H10      -0.5    Perfluorethoxyacetylfluoride                         14  C4F802                                   232.3                                        0    trimethyl-silane     14  C3H10Si                                   74.2 6.7    Trifluormethylpentafluor-2-                         14  C4F802                                   232.03                                        8    oxapropylketone    2-fluoro- 2-methyl-propane                         14  C4H9F 76.11                                        11    pentafluoroethyl-tetrafluoroethyliden-                         14  C4F9N 233.04                                        12.8    amine    2- Trifluoromethyl-propane                         14  C4H7F3                                   112.09                                        13    Perfluor-2-aza-penten-(2)                         14  C4F9N 233.04                                        13.2    fluoro-trimethyl-silane                         14  C3H9FSi                                   92.19                                        16    1,1,1- trifluoro-butane                         14  C4H7F3                                   112.09                                        16.74    dimethyl-vinyl-borane                         14  C4H9B 67.93                                        17.1    Tris-(trifluormethyl)-                         14  C3F10Ge                                   298.61                                        19.1    germaniumfluoride    fluoro-trimethyl-silane                         14  C3H9FSi                                   92.19                                        20    propyl-silane        14  C3H10Si                                   74.2 21.3    1,1,1,3,3,3-hexafluoro-2-methyl-propane                         14  C4H4F6                                   166.07                                        21.5    2- fluoro-butane     14  C4H9FF                                   76.11                                        24    1,1,1,4,4,4-hexafluoro-butane                         14  C4H4F6                                   166.07                                        24.5    methoxy-dimethyl-borane                         14  C3H9B0                                   71.91                                        24.6    trifluoro-propyl-silane                         14  C3H7F3Si                                   128.17                                        25    Deuterio-trimethyl germane                         14  C3H9DGe                                   119.71                                        26    Trimethyl Germane    14  C3H10Ge                                   118.7                                        26    trimethyl-hydroxylamine                         14  C3H9N0                                   75.11                                        30    2,2 difluoro-butane  14  C4H8F2                                   94.1 30.92    1- fluoro-butane     14  C4H9F 76.11                                        31    Tris- (trifluoromethyl)-germaniumchloride                         14  C3ClF9Ge                                   315.06                                        37    nonafluoro-1-nitroso-butane                         15  C4F9N0                                   249.04                                        16    3- methyl-but-1-ene  15  C5H10 70.13                                        20    1,1- dimethyl-cyclopropane                         15  C5H10 70.13                                        20    3- methyl-but-1-ene  15  C5H10 70.13                                        20    1,1- dimethyl-cyclopropane                         15  C5H10 70.13                                        20.6    decafluoro-cyclopentane                         15  C5F10 250.04                                        22.48    1,1,1,3,3,3-Hexafluor-2-nitroso-2-trifluormethyl-                         15  C4F9N0                                   249.04                                        24    propane    ± Trans-1,2-dimethyl-cyclopropane                         15  C5H10 70.13                                        28.2    1,2 dimethylcyclopropane                         15  C5H10 70.13                                        28.8    pent-1-ene           15  C5H10 70.13                                        29    1- Nitroso-4-monohydrooctafluorbutane                         15  C4HF8N0                                   231.05                                        30    trifluoro-acetic acid-                         15  C4F9N0                                   249.04                                        30    (bis-trifluoromethyl-amide)    isopropyl-methyl ether                         15  C4H10O                                   74.12                                        30.77    2- methyl-but-1-ene  15  C5H10 70.13                                        30.95    Perfluorpropylmethylether                         15  C4H3F70                                   200.06                                        34    diethyl ether        15  C4H10O                                   74.12                                        34.6    ethyl-cyclopropane   15  C5H10 70.13                                        35.8    methyl-cyclobutane   15  C5H10 70.13                                        36    pent-2-ene           15  C5H10 70.13                                        36.15    pent-2 c-ene         15  C5H10 70.13                                        36.55    cis-1,2- dimethyl-cyclopropane                         15  C5H10 70.13                                        37.03    2- methyl-but-2-ene  15  C5H10 70.13                                        37.2    beta- Nitroso-nonafluordiethylether                         16  C4F9NO2                                   265.04                                        15    nitrous acid ethyl ester                         16  C2H5NO2                                   75.07                                        17.4    Perfluor-diethylamine                         16  C4F11N                                   271.03                                        23.9    Perfluor-2-aza-pentan                         16  C4Fl1N                                   271.03                                        24.3    4-Methylpent-4-ensaeurenitrile                         16  C6H9N 95.14                                        30    butyl-difluoro-borane                         16  C4H9BF2                                   105.92                                        35    ethyl-dimethyl-amine 16  C4H11N                                   73.14                                        36.4    3,3 dimethyl-but-1-yne                         16  C6H10 82.15                                        37    2,2- dimethyl-propane                         17  C5H12 72.15                                        0.95    (-)(S)-l- fluoro-2-methyl-butane                         17  C5H11F                                   90.14                                        14.1    (-)(R)-2- chloro-pentaine                         17  C5H11Cl                                   106.59                                        24.7    Tetramethyl-stannane 17  C4H12Sn                                   178.83                                        26    2- methyl-butane     17  C5H12 72.15                                        27.85    nonafluoro-2-trifluoromethyl-butane                         17  C5F12 288.04                                        30.12    Tetrakis(trifluoromethyl) germane                         17  C4F12Ge                                   348.61                                        31.7    pentane              17  C5H12 72.15                                        36    __________________________________________________________________________

EXAMPLE 50

In a preferred embodiment, the dispersed phase can be composed of anychemical which has a boiling point under standard pressure conditionsbelow the body temperature of the organism to which the formulation isto be administered and which will be examined following administrationby ultrasound. Example 45 discusses how one selects suitable chemicalsfor the dispersed phase based on the temperature range obtained byconsideration of the boiling point of the selected chemical andparameters of the manufacturing process.

The boiling of pentane (dodecahydropentane) and perfluoropentane(Dodecafluoropentane) are 36°-37° C. and 28°-29° C., respectively. Thisis an excellent temperature range in which to select suitable chemicalsas the dispersed phase. Therefore, chemicals which contain five carbonatoms and variable hydrogen and fluorine atoms will have boiling pointsbetween 28° and 37° C. and will make suitable dispersed phase chemicals.The following listing of suitable chemicals contains some, but not allchemicals containing five carbons, with variable numbers of hydrogen andfluorine atoms, i.e., C₅ H_(X) F_(Y) :

1,3-Cyclopentadiene, 5,5-difluoro-;Cyclobutane,1-fluoro-3-methylene-;2H-Fluorinium;Cyclobutane,(fluoromethylene)-;Methylene, cyclobutylfluoro-;2,4-Cyclopentadien-1-yl,2-fluoro-;2H-Fluorinium, ion(-1),(deloc-2,3,4,5,6)-;6-Fluoroniabicyclo(3.1.0)hexane;6-Fluoroniabicyclo(3.1.0)hex-2-ene,hydroxide, innersalt;Fluorine(2+),1,3-pentadien-1-yl-5-ylidene-;1,3-Pentadiene, fluorinecomplex;Fluoranium;Cyclopentyne, 4-fluoro-;Cyclobutene,3-(trifluoromethyl)-;Cyclopentane,1,1,2,2,3,3-hexafluoro-;Tricyclo(1.1.1.01,3)pentane, fluoro-,ion(1-);Spiro(2.2)pentane, fluoro-, ion(-1);Tricyclo(1.1.1.01.3)pentane,fluoro-;cyclopentane, 1,2-difluoro-, trans-;Cyclobutane,1,1-difluoro-3-methylene; 1,3-Cyclopentadiene,2-fluoro-;1,3-Cyclopentadiene, 1-fluoro-;Bicyclo(1.1.1)pentane,1,3-difluoro-;1,3-Cyclopentadiene, 1,2,3,4,5-pentafluoro-,dimer;1,3-Cyclopentadiene, 1,2,3,4-tetrafluoro; 1,3-Cyclopentadiene,1,2,3,4,5-pentafluoro-;Cyclopentene,1,2,3,3,4,5-hexafluoro-;Cyclobutane,1,1,2,2,3-pentafluoro-3-(trifluoromethy)-;Cyclobutene,3,3,4,4-tetrafluoro-1-methyl-;Cyclobutane,1-fluoro-1-methyl-;Bicyclo(2.1.0)pentane,2,2,3,3-tetrafluoro-;Cyclopentene, 3,3-difluoro-;1,3-Cyclopentadiene,5-fluoro-;Cyclobutane,2-(difluoromethylene)-1,1,3,3-tetrafluoro-;Spiro(2.2)pentane,1,1,2,2,4,4-hexafluoro-;Bicyclo(1.1.1)pentane, 1-fluoro-;Cyclopentene,4,4-difluoro-;Cyclobutane, (difluoromethylene)-;Cyclobutane,1,1-difluoro-2-methylene-;Spiro(2.2)pentane, 1,1-difluoro-;Cyclobutane,1,1,3,3-tetrafluoro-2-methylene-;Cyclobutane,2-(difluoromethylene)-1,1-difluoro-,Spiro(2.2)pentane,1,1,4,4-tetrafluoro-;Cyclopropane,1,1-bis(trifluoromethyl)-;Spiro(2.2)pentane,1,1,2,2-tetrafluoro-;Tricyclo(1.1.0.02.4)butane,(trifluoromethyl)-;Spiro(2.2)pentane, 1,4-difluoro-;Spiro(2.2)pentane,1,2-difluoro-;Spiro(2.2)pentane, fluoro-;Bicyclo(1.1.0)butane,1-(trifluoromethyl)-;Cyclopentane, 1,2-difluoro-, cis-;Cyclopropane,(1,1,2-trifluoroethyl)-;Cyclopropane, (1,1-difluoroethyl)-;Cyclopropane,(1,2,2-trifluoroethyl)-;Cyclopropane, (2,2-difluoroethyl)-;Cyclopropane,(2-fluoroethyl)-;Cyclopropyl, 1-fluoro-2,2dimethyl-;Cyclopropyl,1-fluoro-2,3-dimethyl-, cis-;Cyclobutane,(trifluoromethyl)-;Fluoriranium, trimethyl-;Cyclopentylium,1-fluoro-;Cyclopropane,1,1-difluoro-2-methyl-2-(trifluoromethyl)-;Cyclopropane,1-fluoro-2,3-dimethyl-,(1α,2α,3α)-;Cyclopropane,1-fluoro-2,3-dimethyl-,(1α,2β,3β)-;Cyclopropane,1-ethyl-2-fluoro-;Cyclopropane, 1-ethyl-2-fluoro-, trans-;Cyclopropane,1-fluoro-2,3-dimethyl-,(1α,2α,3β)-;Cyclobutane,1,1,2-trifluoro-2-(trifluoromethyl)-;Cyclopropane,1-(difluoromethyl)-1-fluoro-2-methyl-, trans-;Cyclopropane,1-(difluoromethyl)-1-fluoro-2-methyl-,cis-;Cyclobutane,1,1,2,2,3-pentafluoro-3-methyl-;Cyclobutane,1,1,2,3-tetrafluoro-2-(trifluoromethyl)-;Cyclopropane,(2-fluoroethenyl)-;Cyclopropane,(1-fluoroethenyl)-;Bicyclo(2.1.0)pentane, 5,5-difluoro-;Cyclobutene,1,4,4-trifluoro-3-methylene-;Cyclopropane, 2-etheynyl-1,1-difluoro-,homopolymer;Cyclobutane,3-(difluoromethylene)-1,1-difluoro-;Cyclopropane,1,1,2-trifluoro-2-(trifluorovinyl)-;Cyclopentene,1-fluoro-;Cyclopropane, 2-ethyl-1,1-difluoro-;Cyclopropene,3,3-difluoro-1-(pentafluoroethyl)-;Cyclopropane,1-methyl-2-(trifluoromethyl)-, cis-;Cyclopropane,1-methyl-2-(trifluormethyl)-, trans-;Cyclopropane,1-methylene-2-(trifluoromethyl)-;Cyclopentane,1,1,2,2,3,3,4,5-octafluoro-;Cyclopropane,1-(difluoromethyl)-1-fluoro-2-methyl-, cis-;Cyclopropane,1-(difluoromethyl)-1-fluoro-2-methyl-, trans-;Cyclopentane,1,1,2,2,3,3,4-heptafluoro-;1,3-Cyclopentadiene, 1,2,4,5,5-pentafluoro-,dimer; 1,3-Cyclopentadiene, 1,2,3,5,5-pentafluoro-,dimer;1,3-Cyclopentadiene, 1,2,3,5,5-pentafluoro-;1,3-Cyclopentadiene,1,2,4,5,5-pentafluoro-;Cyclopentane,1,2,3,4,5-pentafluoro-,stereoisomer;Cyclopentane,1,1,2,3,4,5-hexafluoro-,stereoisomer;Cyclobutene,3-fluoro-1-methyl-;Cyclopentene, 1,4,5,5-tetrafluoro-;Cyclopentene,3,3,4,4-tetrafluoro-;Cyclopentene, 3,3,4,4,5-pentafluoro-;Cyclopentene,1,4,4,5,5-pentafluoro-;Cyclopentene,1,3,3,4,4,5-hexafluoro-;Cyclopropane,(2,2,2-trifluoroethyl)-;Cyclopentane,1,1,2,3,3,4,5-heptafluoro-;Cyclobutene, 2,3,3-trifluoro-1-(trifluoromethyl)-;Cyclopentene,1,2,3,3,4,5,5-heptafluoro-;Cyclopentene,1,2,3,3,4,4,5-heptafluoro-;Cyclobutene,3,3,4,4-tetrafluoro-1-(trifluoromethyl)-;Cyclopentene,1,3,3,4,4,5,5-heptafluoro-;Cyclopropane,2-fluoro-1,1-dimethyl-;Cyclopentane,1,1,2,2,3,4,5-heptafluoro-;Cyclobutane,1,1,2,2-tetrafluoro-3-(trifluoromethyl)-;Cyclopentane,fluoro-;Cyclopentene, 1,2,3,3,4,5-hexafluoro-, trans-;Cyclopentane,1,1-difluoro-;Cyclopentane, 1,1,2,3,3,4,5-heptafluoro-,stereoisomer;Cyclopentane, 1,1,2,3,3,4,5-heptafluoro-,stereoisomer;Cyclopentane, 1,1,2,3,3,4,5-heptafluoro-,cis,cis-;Cyclopentene, 1,3,3,4,5,5-hexafluoro-;Cyclopentene,1,2,3,3,4,5-hexafluoro-, cis-;Cyclopentane, 1,1,2,3,4,5-hexafluoro-,stereoisomer;Cyclopentane, 1,1,2,3,4,5-hexafluoro-,(2α,3α,4β,5α)-;Cyclopentane, 1,1,2,3,4,5-hexafluoro-,stereoisomer;Cyclopentene, 1,3,4,4,5,5-hexafluoro-;Cyclopentene,3,3,4,4,5,5-hexafluoro-;Cyclopentene,1,2,3,4,5-pentafluoro-;Cyclopentene,1,3,4,5,5-pentafluoro-;Cyclopentane,1,1,2,2,3,3,4,5-octafluoro-;Cyclopentane,1,1,2,2,3,4,4,5-octafluoro-;Cyclopentane,1,1,2,3,4,5-hexafuoro-;Cyclopropane,2-ethenyl-1,1-difluoro-;Cyclopropane, 1,1-difluoro-2,3-dimethyl-,trans-;Cyclopropane, 1,1-difluoro-2,3-dimethyl-, cis-;Cyclobutane,1,1,2,2-tetrafluoro-3-methylene-;Cyclobutane,1,1,2,2,3,4-hexafluoro-3-(trifluoromethyl)-;Cyclopentane,nonafluoro-;Cyclobutane, 1,1,2,2-tetrafluoro-3-methyl-;Cyclopropane,1,2-bis (trifluoromethyl)-;Cyclobutene,1,3,3,4,4-pentafluoro-2-methyl-;Cyclopropane,1,1-difluoro-2,3-dimethyl-;Cyclopropane,1-methyl-1-(trifluoromethyl)-;Cyclopropane,1,1-difluoro-2,2-dimethyl-;1-Butyne,1,3,4,4,4-pentafluoro-3-(trifluoromethyl)-;1,3-Pentadiene,1,1,2,3,4,5,5,5-octafluoro-;Cyclobutene,1,2,3,3,4-pentafluoro-4-(trifluoromethyl)-;1,3-Pentadiene,1,1,2,3,4,5,5,5-octafluoro-;Spiro(2.2)pentane, octafluoro-;Pentadiene,octafluoro-;1,2-Butadiene,1,1,4.4.4-petnafluoro-3-(trifluoromethyl)-;1,2-Pentadiene,1,1,3,4,4,5,5,5-octafluoro-;Cyclopropane, pentafluoro(trifluorovinyl)-;1,3-Pentadiene,1,1,2,3,4,5,5,5-octafluoro-;1,4-Pentadiene,1,1,2,3,3,4,5,5,-octafluoro-;Cyclopropene,3,3-difluoro-1,2-bis(trifluoromethyl)-;Cyclopentene,octafluoro-;1,3-Butadiene,1,1,2,4,4-pentafluoro-3-(trifluoromethyl);Cyclobutene,1,3,3,4,4-pentafluoro-2-(trifluoromethyl)-;2-Pentyne,1,1,1,4,4,5,5,5-octafluoro-;2-Pentene,1,1,1,2,3,4,4,5,5,5-decafluoro-;1-Butene,1,1,3,3,4,4,4-heptafluoro-2-(trifluoromethyl)-;Cyclopropane,1,1,2,3-tetrafluoro-2,3-bis(tribluoromethyl)-, cis-;Cyclopropane,1,1,2,3-tetrafluoro-2,3-bis(trifluoromethyl)-, trans-;2-Pentene,1,1,1,2,3,4,4,5,5,5-decafluoro-;Cyclopropane,pentafluoro(pentafluoroethyl)-;Cyclopropane,1,1,2,3-tetrafluoro-2,3-bis(trifluoromethyl)-;Cyclopropane,1,1,2,2-tetrafluoro-3,3-bis(trifluoromethyl)-;Cyclopentane, decafluoro-,radical ion (1-);2-Pentene, 1,1,1,2,3,4,4,5,5,5-decafluoro-;2-Butene,1,1,1,2,4,4,4-heptafluoro-3-(trifluoromethyl)-;Pentylidene,1,2,2,3,3,4,4,5.5.5-decafluoro-;1-Butene,1,1,2,3,4,4,4-heptafluoro-3-(trifluoromethyl)-;Pentene,decafluoro-;Cyclobutane, heptafluoro(trifluoromethyl)-;1-Pentene,1,1,2,3,3,4,4,5,5,5-decafluoro-;Cyclopentane,decafluoro-;2-Cyclobuten-1-one, 2,3,4,4-tetrafluoro-;Furan,tetrafluoro-;Silane, tetrakis(trifluoromethyl)-;Silane,trifluoro(nonafluorobutyl)-;Pentane,1,1,1,2,2,4,5,5,5-nonafluoro-;Pentane,1,1,1,2,2,3,5,5,5-nonafluoro-;Pentane,1,1,1,2,2,3,3,4,5-nonafluoro-;Pentane,1,1,1,2,3,3,5,5,5-nonafluoro-;Propane,1,1,1,3,3,3-hexafluoro-2-methyl-2-(trifluoromethyl)-;Butane,1,1,1,2,4,4-hexafluoro-2-(trifluoromethyl)-;Pentane,1,1,2,2,3,3,4,4,5-nonafluoro-;Butane,1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-;Propane,1,1,1,3,3,3-hexafluoro-2,2-dimethyl-;Pentane,1,1,3,3,5,5-hexafluoro-;Butane,1,1,1,2,3,3-hexafluoro-2-methyl-;Pentane, hexafluoro-;Pentane,1,2,3,3,4,5-hexafluoro-;Butane,2-(difluoromethyl)-1,1,1,2-tetrafluoro-;Butane,1,1,1-trifluoro-2-(trifluoromethyl)-;Butane-1-13C,4,4,4-trifluoro-3-(trifluoromethyl)-;Pentane,1,1,1,5,5,5-hexafluoro-;Pentane, 1,1,1,2,3,3-hexafluoro-;Pentane,2,2,3-trifluoro-;Pentane, 2,2,4-trifluoro-;Butane,1,1,1-trifluoro-2-methyl-;Butane, 1,1,1-trifluoro-2-methyl-;Butane,1,2,2-trifluoro-3-methyl-;Butane, 1,3,3-trifluoro-2-methyl-;Butane,2,2,3-trifluoro-3-methyl-;Butane, 1,1,1-trifluoro-2-methyl-;Butane,1,1,2-trifluoro-3-methyl-;Pentane, 1,1,2-trifluoro-;Propane,1,1,1-trifluoro-2,2-dimethyl-;Pentane, 1,1,1-trifluoro-;Butane,1,1,1-trifluoro-3-methyl-;Silane, (nonafluorobutyl)-;Silane, dimethylbis(trifluoromethyl)-;Silane, (difluoromethyl) (fluoromethyl)methyl(trifluoromethyl)-;Silane, bis(difluoromethyl)bis(fluoromethyl)-;Silane,(3,3,3-trifluoro-2-(trifluoromethyl)propyl)-;Silane,trimethyl(trifluoromethyl)-;Silane, trifluoro(1-methylpropyl);Silane,(difluoromethyl) (fluoromethyl) dimethyl-;Silane,tris(fluoromethyl)methyl-;Silane, (1,1-dimethylethyl)trifluoro-;Silane,trifluoro(2-methylpropyl)-;Silane, methyl(3,3,3-trifluoropropy)-;Silane,butyltrifluoro-;

EXAMPLE 51

In a preferred embodiment, the dispersed phase can be composed of anychemical which has a boiling point under standard pressure conditionsbelow the body temperature of the organism to which the formulation isto be administered and which will be examined following administrationby ultrasound. Example 45 discusses how one selects suitable chemicalsfor the dispersed phase based on the temperature range obtained byconsideration of the boiling point of the selected chemical andparameters of the manufacturing process.

Fluorocarbons, because of their low toxicity, good emulsificationproperties, and low water solubility, leading to persistentmicrobubbles, are especially suitable as chemicals from which to selectthe dispersed phase. The following fluorocarbons are especiallysuitable: 1,2,2-tris (trifluoromethyl) propane • 2,2-bis(trifluoromethyl) propane • 2-methyl-2 trifluoromethyl propane •tetrakis (trifluoromethyl) silane • methyl tris (trifluoromethyl) silane• bis (trifluoromethyl) dimethyl silane • trifluoromethyl trimethylsilane 1,1-bis (trifluoromethyl)-2,2,3,3-tetrafluoro cyclopropane •1,1-bis (trifluoromethyl) cyclopropane • 1,1-bis (trifluoromehtyl) 2,2difluoro cyclopropane • 1,1-dimethyl (-2,2,3,3)-tetrafluoro cyclopropane• 2,2 difluoro 1-methyl-1-trifluoromethyl cyclopropane • 1,2-bis(trifluoromethyl)-1,2,3,3 tetrafluoro cyclopropane (cis+trans) • 1,2-bis(trifluoromethyl)-1,2-difluoro cyclopropane (ccs+trans) • 1,2-bis(trifluoromethyl)-3,3 difluoro cyclopropane • 1,2-bis (trifluoromethyl)cyclopropane (ccs+trans) 1,1,2,2,4,4,5,5-octafluoro spiro 2.2! pentane •1,1,2,2,-tetrafluoro spiro 2.2! pentane • 1,1,4,4-tetrafluoro spiro 2.2!pentane • 1,1,5,5-tetrafluoro spiro 2.2! pentane • 3,3,4,5 tetrafluorofurar • tris (tri fluoromethyl) phosphire • 1,1,2,2,3,3,4,4,5,5,decafluoro cyclopentane 1,2,2,3,4,4,5,5-octafluoro bicyclo 1.1.1!pentane • 2,2,4,4,5,5 hexafluoro bicyclo 1.1.1! pentane •1,2,2,3,4,4-hexafluoro bicyclo 1.1.1! pentane • 1,2,2,3-tetrafluorobicyclo 1.1.1! pentane 2,2,3,3-tetrafluoro bicyclo 1.1.1! pentane •1,2,2,3,3,4,4-pentafluoro-1-trifluoromethyl cyclobutane,2,2,3,4,4-pentafluoro-1-trifluoromethyl bicyclo 1.1.0! butane,2,2,4,4-tetrafluoro 1-trifluoromethyl bicyclo 1.1.0! butane • bicyclo2.1.0! pentane.

EXAMPLE 52

The utility of high vapor pressure chemicals with boiling points above37° C., that is, which are not low boiling liquids, as the dispersedphase component in a colloidal dispersion was tested as an ultrasoundcontrast agent. The following emulsions were formulated and testedaccording to methods described in Example 18.

    ______________________________________               Vapor        Enhancement Compared to    Dispersed Phase               Pressure (20°C.)                            1-iodoperfluorooctane    ______________________________________    Perfluorohexane               150 mm Hg    2967%    Perfluorooctane                45 mm Hg     400%    ______________________________________

Perfluorononane, with a vapor pressure of about 20 mm Hg at ambienttemperature, would also be expected to show utility in the colloidaldispersions of this invention.

EXAMPLE 53

The objective of this study was to evaluate the potential that anintravenous administration of the emulsions of the invention, at doseseffective in producing ultrasound contrast, to New Zealand White rabbitswould produce the hyperinflated non-collapsible lung (HNCL) syndrome.HNCL syndrome has been produced by a number of fluorocarbon emulsions,including 20% Fluosol®, an F.D.A.-approved intravascularperfluorochemical emulsion (described in patent JP 1609986 andincorporated herein by reference), emulsions containingperfluorooctylbromide (described in patent U.S. Pat. No. 4,987,154 andincorporated herein by reference), and other fluorocarbon emulsions(described in patents or applications EP 231091, JP 63060943, U.S. Pat.No. 4,859,363, U.S. Pat. No. 5,171,755, and JP 21196730, incorporatedherein by reference). The mechanism of HNCL syndrome production, itspotential reversibility, and the clinical significance are not known.The syndrome is characterized by lungs which are hyperinflated atnecropsy, have an increased total volume, a decreased mean density, andcontain detectable quantities of the administered fluorocarbon in thetissues. Leland Clark, the discoverer of HNCL, has stated (Clark L C, etal., Biomat., Art. Cells & Immob. Biotech., 20, 1085-1099, 1992,incorporated herein by reference) that "if HNCL occurs in other species(i.e., humans), then only fluorocarbons boiling above 150° C. can beconsidered safe."

Four groups of male New Zealand White rabbits (3 per group) wereintravenously administered the emulsion of Example 44 at 0.2 or 1.0mL/kg bodyweight, Fluosol (Alpha Therapeutic Corp.) at 24 mL/kgbodyweight, or saline at 24 mL/kg. The doses were selected based on adose which produces ultrasound contrast. Body weights, food consumption,and clinical observations were made during and immediately followingadministration. Twenty-four hours after administration the rabbits wereeuthanized, the lungs excised, and the degree of inflation graded, theweights and volumes of the lungs measured, and the presence ofperfluorocarbons in the tissue determined by gas chromatography, using ahead space analyzer.

The lungs of rabbits receiving saline, or the emulsion of Example 44were normal at necropsy, collapsing upon opening the thorax. The lungsof the rabbits receiving Fluosol showed moderate to severe inflation.

There were no treatment-related changes among the groups in lung weightsor lung-weight-to-bodyweight ratio. The lung volume,lung-volume-to-bodyweight ratio, and lung density measurements in therabbits administered the emulsion of Example 44 were unchanged comparedto controls. The administration of Fluosol lead to a 175% increase inlung volume, a 185% increase in lung-to-body weight ratio, and a ₄₅ %decrease in lung density when compared to controls. These changes werehighly significant (p=0.001).

Dodecafluoropentane was not detected during analysis of lung tissue fromany animal in the group receiving the emulsions of Example 44. Fluosolcontains four major peaks and one minor peak by gas chromatographicanalysis. All five peaks were found in gas chromatograms of headspacetissue samples from animals receiving Fluosol.

Under the conditions of the study, a single administration of theemulsion of Example 44 at dosages producing excellent ultrasoundcontrast showed no effect on lung inflation, weight, or density, did notyield detectable levels of dodecafluoropentane in lung tissues, and isnot considered to cause the hyperinflated non-collapsible lung syndromein the rabbit.

The emulsions formed by the methods described in the prior art producedthis unsafe condition at doses which were necessary to produceultrasound contrast, while surprisingly, emulsions with fluorocarbonswhich boil as low as 29° C., formulated by the methods described in theinstant application, did not produce HNCL.

EXAMPLE 54

A pharmacokinetic study was performed in beagle dogs administered asingle intravenous dose of the emulsion of Example 44 over 5-8 secondsat 0.05, 0.10, and 0.15 mL/kg by obtaining multiple, timed blood samplesand quantifying the dodecafluoropentane content by a validated gaschromatography assay. Twenty-four dogs, twelve males and twelve females,were studied in three dosage groups.

The data was fitted to a two compartment model with a bolus input and afirst order output. There was no significant difference when comparingthe males and females separately or when comparing the three dosagegroups.

The distribution phase varied from 0.9 to 1.3 minutes. The eliminationphase varied from 30 to 48 minutes. The t_(max) (time to maximumconcentration in the second compartment) varied from 5.1 to 6.6 minutes.These elimination times are compared to the elimination times offluorocarbon emulsions of the prior art which are measured in months(see Clark et al. above). Clearly an imaging agent which clears the bodyin a matter of hours is preferred.

EXAMPLE 55

Emulsions of dodecafluoropentane (boiling point 28°-29° C.), a mixtureof dodecafluoropentane and decafluorobutane with a boiling point of20.0° C., and perfluorocyclopentane (boiling point of 22.5° C.) wereformed and their echogenicity tested. The emulsions contained Fluorad170 C as surfactant and were formed by applying acoustic energy from awaterbath sonicator. Echogenicity was tested by adding 0.2 mL of eachemulsion to 1000 mL of water at 37° C. through a 1.2 micron filter andmeasuring the videodensity by the methods described in Example 1. Theemulsion containing dodecafluoropentane produced a grayscale intensitysix seconds following administration of 58.5 units (background of 2.9),the mixture of fluorocarbons produced an increase of 3.0 to 133.3 underthe same conditions, and the perfluorocyclopentane produced the greatestincrease, of from 3.6 to 158.9. Thus, the lower boiling fluorocarbonsproduced greater echogenicity than the higher boiling fluorocarbons.

EXAMPLE 56

Useful ultrasound contrast agent formulations are formed by stabilizingdispersions of a high vapor pressure chemical with emulsions containinga dispersed phase which is composed of chemicals which themselves do notvaporize to an appreciable extent at the body temperature of an organismundergoing an ultrasound examination. For example, fluorocarbon- orhydrocarbon-containing emulsions which are composed of high boilingdispersed phases, as described in U.S. Pat. No. 4,767,410, U.S. Pat. No.4,987,154, JP 2196730, JP 1609986, JP 63060943, and EP 245019,incorporated herein by reference can form the basis of a formulation inwhich the backscatter efficiency is greatly enhanced by the addition ofa high vapor pressure chemical. For example, lecithin-stabilizedperfluorooctylbromide emulsions have significantly increasedechogenicity if perfluoroccyclopentane (boiling point=22° C.) is addedto the dispersed phase prior to comminution. Other low boiling organichalides, hydrocarbons, or ethers have the same effect.

Although the invention has been described in some respects withreference to specified preferred embodiments thereof, many variationsand modifications will be apparent to those skilled in the art. It is,therefore, the intention that the following claims not be given arestrictive interpretation but should be viewed to encompass suchvariations and modifications that may be routinely derived from theinventive subject matter disclosed.

What is claimed is:
 1. A storage-stable injectable formulation forbiomedical use comprising a sterile emulsion of perfluoropentanedispersed in an aqueous carrier by a stabilizer comprising afluorine-containing amphiphilic surfactant selected from the groupconsisting of telomer B containing fluorinated surfactants,perfluoralkyl sulfonate surfactants, perfluoroalkylpoly(oxyethylene)surfactants, fluoralkylthio-ether poly(oxythylene) surfactants,perfluoralkylated polyhydroxylated surfactants, and mixtures thereof. 2.The formulation of claim 1 wherein said amphiphilic surfactant isanionic.
 3. The formulation of claim 1 wherein said amphiphilicsurfactant is present at a concentration between 0.001% and 6.0% byweight per volume.
 4. The formulation of claim 1 wherein saidformulation further comprises a viscogen present at a concentrationsufficient to produce a viscosity of said formulation greater than 1.1cP.
 5. The colloidal dispersion of claim 1 wherein the concentration ofsaid perfluoropentane in said formulation is between 0.05 and 5.0% byweight per volume.
 6. The formulation of claim 1 wherein saidfluorine-containing amphiphilic surfactant is selected from the groupconsisting of telomer B containing fluorinated surfactants.
 7. Theformulation of claim 1 wherein said fluorine-containing amphiphilicsurfactant is selected from the group consisting of perfluoroalkylsulfonate surfactants.
 8. The formulation of claim 1 wherein saidfluorine-containing amphiphilic surfactant is selected from the groupconsisting of perfluoroalkylpoly(oxyethylene) surfactants.